A 70mm finish plane. Blade by Mr. Takeo Nakano, body by Mr. Isao Inomoto
The way of the carpenter is to become proficient in the use of his tools, first to lay his plans with true measure and then perform his work according to plan. Thus he passes through life.
– Miyamoto Musashi, The Book of Five Rings
his is the sixth article in our series about Japanese handplanes. In previous installments we compared Western and Japanese planes and discussed how to tune and adjust the Japanese hiraganna plane. In this article your humble servant will be so bold as to explain how to setup and maintain the sole of the Japanese handplane.
The sole of a handplane is critical because it positions the blade’s cutting edge in relation to the board being worked making it possible to cut useful shavings of the desired thickness and length. Sometimes we want to cut thick shavings to quickly remove material from a board when flattening and/or dimensioning it, the job of the arashiko plane (荒仕子鉋). Sometimes we want to take ultra-thin shavings to create a flat, smooth, even shiny surface, the job of the finish, or shiage plane (仕上げ鉋). One plane cannot do it all, nor can a single type of sole setup.
In this article we will consider ways to setup the sole of a Japanese plane for Beloved Customer’s specific purpose. We will also examine ways to maintain the sole and the necessary tools.
Miyamoto Musashi, the famous swordsman, duelist, artist, philosopher and author. 1584 – 1645. Well-known for appreciating the work of carpenters and for slicing and dicing using two swords simultaneously.
Soleful Profiles
Besides keeping the cutting edge properly positioned to take shavings the handplane’s sole has another important role many overlook. We examined this in Part 5 of this series. In summary, to cut efficiently and minimize wasteful tearout on the surface of a board being planed, a contact strip approximately 3-6mm wide located directly in front of the mouth opening must apply uniform pressure on the surface of the board. This important principle is effective in the case of all handplanes of all countries made of all materials be they organic or metallic.
Indeed, depending on one’s skill with a handplane (there’s more than just pushing and pulling involved, after all), so long as this strip on the sole is applying even pressure to the board right up to the mouth opening, the rest of the sole can be pretty wonky and still yield good results with little or no tearout. And while this level of skill comes of experience, it all begins with understanding the aforementioned principle.
Beloved Customer is not doubt aware that the basic, standard sole configuration for handplanes is a simple flat surface free of wind. A little different from the adjustable bed of an electrical jointer, of course. While all handplanes wear and require constant maintenance regardless of their construction, wooden-bodied planes are softer than metal-bodied planes and tend to wear and warp more in use, the price we must pay for the advantages of the wooden body.
The wise man, therefore, will strive to discover ways to make the necessary task of truing the sole of his planes as easy as possible, a mindset clearly reflected in the Japanese version of the wooden bodied handplane giving it a huge advantage over its Western counterparts, at least in the hands of the thoughtful and diligent craftsman. Sadly, many newbies and all wood butchers poorly understand how the sole of the handplane works, or fail to set it up properly, or fail to maintain it properly blaming the plane when it stops working instead of themselves. So sad. So self-defeating.
Well-made Western planes ideally have a uniformly-flat sole. But is it really necessary to have the entire area of the sole in contact with the surface of the board being planed? Please consider this question in light of my earlier statement about the most important part of the sole being the contact strip directly in front of the mouth.
Japanese craftsmen decided long ago that it’s most efficient to relieve (remove) areas of the sole located between two or three critical contact points on the sole thereby making it much easier and quicker to true the soles of their planes, while at the same time significantly reducing friction, both significant advantages springing from a simple modification. This is much the same principle as the hollow-ground ura in the blades of Japanese planes, chisels and knives. The application of this principle results in two basic profiles to plane soles described below.
While lots of graphics would be nice, I beg Beloved Customer’s indulgence with the one I have available.
The Sole of the Arashiko Plane
The first and most common profile, illustrated below, is applicable to all planes intended for creating straight, flat surfaces, including the arashiko plane as well as the various types of jointer (nagadai) and shooting (suridai) planes. Finishing planes have a different sole profile described in the next section.
Upside-down cross-sectional illustration of a standard plane intended for producing flat surfaces. Length of the full-width contact strips A, C, D = approximately 6-10mm. Relief a = b = approximately 0.2~0.5mm
Contact area “C” is a strip of the sole located directly in front of the mouth and the full-width of the sole, and is the single most important detail of the sole. Contact area D is also a full-width contact strip located at the leading edge of the sole. And contact area A is located at the trailing edge of the sole. It’s very much a matter of personal preference, but a length of 6-10mm is typical for these contact areas.
The crosshatched areas in the drawing indicate where the sole has been scraped away leaving it hollow or “swamped.” These areas do not contact the surface of the board being planed. The precise shape of these swamped areas between A and B and C and D is unimportant, but it’s best if they are relatively uniform and approximately 0.2-0.5mm deep. Once again, personal preference.
Please note that point B, and the portion of the sole immediately behind the blade, is always relieved and never contacts the board being planed. This is important because if it does contact the board, vexing problems often result. Most people get this wrong at least once, or fail to perform proper maintenance allowing this swamped area to bottom-out whereupon the usual undignified weeping, wailing etc. ensues. You’ve been warned.
This arrangement gives the plane three supporting strips, and because the front and rear contact strips are located at the extreme ends of the plane, the full-length of the plane’s body will act as a jig so the plane will tend to shave off the tops of high spots and skip over low spots producing a straight/flat surface quicker and more precisely than a simple flat, planer (meaning “lying in a single plane”) sole typically will. You will notice the difference if you pay attention.
This arrangement also makes it very easy to adjust the sole to keep the critical contact strip in front of the mouth in tight contact with the board being planed.
Some people like to add another contact strip, or even two, between C and D. This works well tending to slow down wear on the sole, but it is a fiddly detail most people don’t bother with.
But as so much in life, not all is not blue bunnies and fairy farts for this arrangement of three or more contact strips tends to lift the cutting edge up and away from the surface being planed when they pass over even tiny irregularities on the board’s surface. This is hunky-dory in most cases, but once the board is as flat as we need it to be, this porpoising movement over every tiny irregularity, especially if the blade is set to take a fine shaving, can become counterproductive to producing a smooth, shiny surface. So how best to setup the sole when we need our plane to do more smoothing and finishing than truing and flattening?
The Sole of the Finishing Plane
I apologize for not having a pretty illustration, but Beloved Customers are, without exception, highly intelligent and intuitive souls (no pun intended) so I’m confident a simple written description of the difference between the sole of a finishing plane and the one described above will suffice.
That difference in the soles of these two types of plane is simply that the sole is entirely swamped from the heel of the plane (contact strip A) to the mouth opening. In other words, contact strips C & D remain unchanged but contract strip A is completely shaved away. That simple.
For example, the overall length of the dai (body) of the finishing plane body cut by Mr. Inomoto I have in my hand as I write this (gotta be careful to not drop it on my inkpot!) is 280mm. If setup as an arashiko or flattening plane, the effective planing distance would be the entire length of the plane’s sole. In this case, however, Mr. Inomoto has it set it up as a finishing plane so he has swamped/relieved the entire sole from the mouth opening to the heel (Point A to Point B), approximately 108mm. The effective length of the sole for purposes of flattening measured from toe to mouth therefore is 173mm, a 38% reduction.
Why bother with a measly 173mm you ask? Ah, Beloved Customer is especially perspicacious today!
Since the effective jig length of the sole is reduced 38%, and the cutting edge is located at the extreme tail end of that area, the cutting edge will tend to more closely follow irregularities in the board’s surface riding them up and down and in and out instead of bridging and porpoising over them allowing the blade to cut long, uniform shavings without the interruptions that would otherwise result from the sole riding the tops of residual irregularities in the board’s surface lifting the cutting edge up and out of contact with the board when we need it to more closely follow the contours of the board. It’s a genius concept that works well in application.
But of course that malevolent monster Murphy always insists on probing with his pointy purple pecker to defeat all good things, so if this arrangement stops working for you, be sure to check the following three details in your plane:
Your blade is sharp;
The 2 or three contact strips you have provided (more if you like multiple swamps) are truly planar (in the same plane);
And most importantly, the contact strip in front of the mouth is flat and in uniform contact with the board being planed. I can’t stress too heavily the importance of this little patch of wood.
Here is Wisdom: When setting-up and maintaining the sole of a Japanese plane always always always give the contact strip in front of the mouth highest priority, while at the same time minimizing any shaving/scraping you do to it.
Why is your humble servant so irritatingly picky about minimizing shaving/scraping at this contact strip? More of that bloody, demon-chewed, hard-earned wisdom: While wear is inevitable, any scraping/shaving you do to this contact strip will open up the mouth further reducing the plane’s useful effectiveness at taking fine shavings (think about it). This isn’t so much a problem for an arashiko, truing, or jointer plane but it imposes a significant detriment to the quality of a finish plane’s work. So don’t diddle with the mouth contact strip more than is necessary unless you enjoy inletting replacement mouths.
Tools and Techniques for Sole Setup and Maintenance
You’ll need the following tools, at minimum, for initial setup and periodic maintenance of your Japanese hiraganna handplane:
A sharp handplane that can cut a smooth, flat surface. For a 70mm handplane, you really need an 80mm handplane, but with care narrower planes can also do the job. Don’t let it become a chicken and egg problem.
A scraper tool of sorts. I prefer a simple card scraper, an ancient and uniquely Western tool that the Kezuroukai has borrowed and made popular in Japan recently. You’ll need a burnishing tool of sorts to turn the burr. A wide chisel can also be used as a scraper, although it’s hard on the tool’s edge. I was taught to maintain a plane’s sole using either a chisels or the traditional “dainaoshi” plane, aka “tachiganna,” essentially a small scraper plane. These tools work well enough, but the card scraper works better IMHO. Over the years I’ve learned several tricks to improve the performance of these little planes from advanced Japanese joiners, but even then, the downside to the scraper plane compared to the card scraper or even a chisel is that the sides of the plane, and the koppagaeshi for that matter, obstruct the the view of the blade sometimes making me unsure exactly where the blade is shaving in relation to the critical mouth and the other contract areas. Also, it does not work as well when scraping the swamped areas with the grain because the longer body tends to create a flat surface which I don’t necessarily need. The result is that these scraper planes are used mostly to shave cross-grain across the width of the sole leaving a rougher surface. With a card scraper, on the other hand, I can always see the exact position of the blade at all times, and it shaves wood reliably both with the grain and cross-grain while leaving a smoother surface behind. It’s just a superior solution.
A straightedge. The classic Japanese tool for this job is the wooden “shitaba awase jougi” 下端合定規. More on it below. A better more modern tool is the hardened, stainless steel, beveled-edged, notched precision straightedge made by Matsui Precision. This tool has the huge advantage of being able to check the sole for straight, flat and wind with the blade installed and its cutting edge projecting through the mouth the appropriate distance.
Glass plate. A piece of minimum 3/8″ (10mm) thick float glass longer than the sole of your plane.
A pencil.
A small square.
A dainaoshi scraper plane, also called the “tachiganna.”
Procedures
Check the Sole: The first step is to use your straightedge to check that the sole is straight, flat and free of wind. Install the blade and chipbreaker with the cutting edge projecting through the mouth just as it will be when the plane is used. This is important because the wedging action of the blade can cause the body to warp slightly. If you don’t have a notched straightedge and don’t want to make one yourself, insert the blade so the cutting edge remains recessed in the mouth without projecting. 0.001″ is probably OK. Check the sole lengthwise, crosswise, and multiple diagonals.
True the Sole: When initially setting-up or drastically redoing the sole of a wooden handplane, after making the checks listed in No. 1 above, you must make the sole absolutely flat and free of wind (twist) using your handplane and/or scraper and your precision straightedge. You may need to remove and reinstall the blade and chipbreaker several times to get this right. An alternate, but disgusting, technique is to use sandpaper and the float glass mentioned above supported on a stable, flat surface like the bed of a electric jointer or tablesaw to flatten the sole. Be sure to recess the cutting edge slightly. Don’t remove more wood than is absolutely necessary. Check for flatness and wind frequently.
Layout the Contact Strips & Swamps: Use your pencil and square to layout the locations of the contact strips. Then use your pencil to crosshatch the areas to be swamped.
Relieve the Swamp/Crosshatched Areas: With the blade and chipbreaker installed, use your scraper, chisel, or dainaoshi plane to scrape away the appropriate amount of wood from the hollow, swamped areas. Be careful to not let your metal tools touch the blade of your plane.
Check the Sole: With the blade and chipbreaker installed but slightly recessed into the mouth, check how it feels on the supported plate glass. The plane should not rock or roll when you push down on its ends or corners, depending of course on the sole setup you chose and where you push. If it does rock rub a itsy bitsy teeny weeny bit of oil on the glass, place the plane sole-down on it, and move it around a few millimeters. Then check the oil transferred to the sole to determine areas of contact. It may help to add a little graphite from your pencil to the oil to make the contact areas show up better. The most important goal is uniform contact at the strip in front of the mouth.
Refine the Sole: Use your scraper tool to carefully remove material preventing uniform, full-width contact at the mouth. If at all possible, accomplish this by removing material from the other contact strips first. Make only tiny adjustments while sneaking up on the final surface like a tiny, needle-clawed, big-eyed kitten stalking a grasshopper. This is important. During this process recheck the sole with your straightedge and glass plate frequently.
The Shitaba Awase Jogi 下端合わせ定規
The shitaba awase jougi is the first tool I was required to make for myself during training in Japan. This was once standard procedure in all woodworking trades.
It’s simply two sticks of wood, usually cut bookmatch from a single piece of stable, quartersawn soft wood, connected face to face with two dowels or dovetail tenons. If you shoot one edge of this tool with a jointer plane when the two halves are joined, then separate them and hold them up to a light source with their edges butted together, the gap between the two edges will reveal double the error. By rejoining the halves, carefully planing/scraping their edges, and frequently rechecking the gap, one can consistently create two high-precision straightedges that won’t damage your plane blade. The webpage at this link shows how to make one version. It’s a lifetime tool.
When using your plane, sure as eggses is eggses the time will come when you will discover it’s stopped working, usually right at the the most inconvenient time for Murphy will have his way. At that juncture weeping, wailing and gnashing of teethses may ensue! When this happens remain calm and consider the experience for what it is: another step on the path to mastery. Then gird up your loins, really tight so the boys start to complain, and simply follow the three steps listed above. All will be well, I promise.
In the next installment in this series of inklings about stealthy kittens and Murphy’s pointy purple poisonous pecker we will discuss how to use the Japanese handplane, a task many people unwittingly get wrong. Y’all come back know y’hear!
YMHOS
Two 18′ tall Nio wood carvings. Serious woodworking!Guess which one’s Mutt and which is Jeff.
If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.
Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or or the IT manager for HRC’s bathroom server farm, and so won’t sell, share, or profitably “misplace” your information. If I lie may all my swamps be infested with toxic, arrogant, bellowing, wart-covered bullfrogs, as is the US Congress.
An old-fashioned adjustable chamfer plane. It lacks the convenient screw adjusters of the modern version, but it does a fine job nonetheless.
The edge separates the average from the exceptional.
Anon
In this installment in our series of articles about Japanese handplanes, your most humble and obedient servant would like to present one of the most useful woodworking tools of Japan, the adjustable chamfer plane.
Terminology
In Japanese this handplane is called a kadomenganna, written 角面鉋 in Chinese characters. “角Kado” means “corner,” “面 men” means “surface,” and “鉋 ganna” is a tweaked pronunciation of “kanna” which means “handplane.” Since it’s mainly used to cut 45˚chamfers on the 90˚ corners and edges of wooden objects, and being fully adjustable, I choose to call it an “adjustable chamfer plane” in English. I beg Gentle Reader’s kind undulgence.
Side view of a standard kakumenganna chamfer plane.
Top view of a new kakumenganna chamfer plane. Of course, the 2 Chinese characters stamped on its leg read, top to bottom, “kadomen.” This version has a slightly skewed blade to reduce tearout. The blade and chipbreaker are mounted in a movable block connected to the right and left legs by a tongue and groove joint forming what I call a “carriage.” These two legs serve as fences which can can be opened or closed, using the bolts and nuts seen, to adjust the gap which determines the width of the chamfer to be cut. You can see two graduated brass bars inlet into the legs to help with alignment and in judging the gap.
Components
Your humble servant’s old and well-used chamfer plane. The block which houses the blade is located to the left of the image with two fences I call legs in the middle. Together these form a “carriage.” The horizontal line in the center of both legs was cut by the blade as I shifted the carriage right and left.A side view of the block (left), the underside of the legs (center), and back of the blade (lower right). The cedar block (upper right) is used to adjust the block and remove the blade in combination with a smallish wooden mallet.You can see the brass mouth reinforcement inlet into the sole of the block. This is very important for a chamfer plane that will see heavy use shaping various materials. Although it has become dim over the years, the line drawn across the legs indicate the position of the blade, an important point to watch for when starting and stopping some cuts.
I’m sharing these photos of my old plane as a practical example. When new, the edge of the blade’s head had a sharp burr which I filed down for comfort. This is a type of plane that does not take ham-handed abuse from fools well. Please note that, unlike most such planes used by less knowledgeable folk, the head of the blade is not mushroomed and the blade’s face is not dinged. Why? I have never struck this plane, purchased in 2009, with a steel hammer, not even once. For the same reason the wooden parts, while discolored and less-than-perfect through much use, exhibit none of the deformation, cracking, splitting, chipping and denting planes adjusted using steel hammers always do. This is the fruit of wisdom shared with me by an ancient plane maker on Shikoku island far back in the mists of time (ツ). Rejoice! You and your planes are now free of the chains of ignorance.
The modern Japanese chamfer plane, which is the only type we currently carry, is comprised of a small block of white oak housing a relatively narrow laminated steel blade as well as a chipbreaker.
This block (aka “dai” 台 in Japanese) fits into a “carriage” comprised of two sticks of white oak joined by steel and brass nuts and bolts held in place by captured wing nuts. The block fits tightly into grooves cut into the carriage so the user can shift the block and its blade right or left as necessary to either accommodate the required width of cut, or to expose a sharp portion of the blade when one portion becomes dull.
The width of cut can be quickly adjusted from zero to 24mm wide by rotating the two wing nuts smoothly opening or closing the gap between the two legs of the carriage. Eazy peazy Japaneezy.
The most common variety of chamfer plane has a blade inlet into the block with its mouth oriented 90˚ to the direction of travel. The next most common variety has a blade that is slightly skewed to produce a smoother cut with less tearout. We carry both types.
Standard chamfer plane (left) and skewed chamfer plane (right).
Uses for the Chamfer Plane
Japanese chamfer planes are essentially molding planes with two mutually adjustable fences used to produce chamfered edge treatments on wooden objects. Molding handplanes typically have blades ground to specific profiles intended to plane the edges and corners of wooden objects. Some produce purely decorative, curved shapes such as the Roman ogee, while others produce functional and/or structural edges such as tongue and groove joints.
But 45˚chamfer planes have a simple straight blade intended to produce a flat surface at 45˚ to the adjacent faces of the board. However, some varieties are used to cut chamfered surfaces at various angles.
The ancient, attractive and functional lambs tongue chamfer stop use in wood, stone and ivory.
Once cut this 45˚ chamfer is often left as-is in many projects and especially structural wood members as a finished surface. It tends to make make the board, beam or column look more refined. It also prevents the corners from being easily chipped or torn off, a safety feature in some cases. A hard 90˚ corner in exposed wood is seldom durable and given time and abuse often becomes ouchy.
Nowadays the electric router has sadly replaced practically all molding planes, and although I haven’t used an electric router in 15 years or so, I won’t deny they are very useful tools even if they are ultimately more expensive, destroy the user’s inner peace along with their hearing, fills their lungs with dust, chews their fingers, leaves unsightly ripple marks on the wood, and goes through expensive bits like Homer Simpson does donuts… mmmm donuts.
But routers are not all evil, for they do have the advantage of being able to treat the inside surfaces of curved edge whereas the plane under consideration can only do straight edges and outside curved surfaces. Of course, it’s possible to make chamfer planes that cut inside curved surfaces like those used by coopers (barrel makers).
The Joinery Chamfer Plane
An old but unused chamfer plane for kumiko and cabinet sash with wooden adjustment screws.
Chamfers cut on standard kumiko. Being much less than 45˚, this angle gives the kumiko a refined appearance.Even thinner kumiko with yet a different chamfer angle. Assembly of such continuous kumiko can be challenging.
As mentioned above there are a very few varieties of specialty chamfer planes long used in joinery to produce different angles. Why angles other than 45˚ you say? Ah, perspicacious as always. Well, a simple 45˚ chamfer sheds dust and water well, but in the case of windows, doors and shoji, for example, it removes too much wood weakening mullions and kumiko to the point of structural frailty, and often appears less refined to boot. Sadly, these are no longer being made and are hard to find.
Advantages
As I suggested above, the chamfer plane produces lots of of fragrant shavings but little unhealthy dust. It won’t make your fingers bleed, and won’t grab your clothes.
Indeed, I can still remember the night I was working late on a custom door using a 15amp 1/2″ collet electrical plunge router with a long 3/4″ Ø carbide bit to cut deep mortises. This was before the days of automatic mechanisms to stop the spinning mass of copper and steel that is the armature when the power switch is released. Suddenly, out of pure evil malice, the howling beast grabbed my loose soccer jersey nearly chewing a hole in my chest! Ah, good times!
The chamfer plane works slower than a router, but it won’t gouge your work if you loose concentration for a second, it won’t make burn marks on your boards, or cause She Who Must Be Obeyed to lob complaints about racket and dust at you like barbed arrows smeared with toxic tree frog goop. To the contrary, it’s an efficient, well-behaved, forgiving, even gentle tool, one that produces a flat, sometimes even shiny surface with perfectly crisp edges on wood instead of the burnt and pounded washboard surfaces violent routers often inflict.
Another advantage to the Japanese chamfer plane is its relative light weight and small bulk, compared to the bulky, clunky, mind-numbing electrical equivalent. Much easier to store in the toolbox or work apron. And of course, being a simpler and more honest tool, it’s much less likely to be commandeered by Murphy’s painful pointy purple pecker to wreak death and destruction.
And of course, while its blade does need to be sharpened occasionally, the chamfer plane will provide many decades of continuous service without having to purchase a single nasty spinning bit from the CCP.
While it incorporates a couple of bolts, it has no cord and needs neither piggish chargers, nor poisonous batteries. It is a tool in total denial of the principles of planned obsolescence, predetermined service life, corporate profitability and hidden environmental destruction advocated by the high priests of profit at the Harvard School of Business and Monkey Butts. One might even say it’s a pragmatically contrarian tool. But whatever you choose to call it, I call mine a faithful servant, indeed, a friend.
How to Adjust
Adjusting the width of the chamfer is accomplished by first loosening the two wing nuts on the bolts. If increasing the width of cut, continue to spin the wingnuts out. Then once the gap between the legs is the right width, set the locknuts to the right position, check that the legs are parallel either by using a caliper to measure the distance between the legs at the front and rear of the carriage, and lock the legs in place using the wingnuts.
These planes have graduated brass indicators inlaid across the front legs and another across the rear sides of the carriage that are useful for rough use, but should not be relied on for precise settings.
Alternately, you can rest the plane on the corner of the board and examine the gap between the legs and board. If a significant gap exists, simple adjust the wing nuts until it closes.
When considering the purchase of a chamfer plane, be sure it has a brass plate inlaid in front of the mouth to prevent wear at this high-pressure area.
When you receive your chamfer plane, the block should fit tightly into it’s carriage. This will loosen with use, or applying a bit of oil or wax on the tongues of the block will help. Worse case, use a metal file and a bit of 220grit sandpaper to lightly adjust the width of the tongue.
When removing the block from the carriage, please do not use a steel hammer to strike the block. A wooden mallet works well, but holding a small block of softwood, like the one shown in the photo above, as a cushion between hammer/mallet and plane is best.
A Professional Technique
Quite frequently we need to cut a stopped chamfer, whether it’s for a lambs tongue chamfer detail or where stile meets rail in joinery. In any case, when we need to judge exactly where the blade of our planes starts and stops a cut, it helps to make marks on the chamfer plane’s legs indicating the location of the cutting edge, and corresponding pencil marks on the workpiece, to help with starting and stopping chamfer cuts in the right place.
Summary
The Japanese kakumenganna 45˚chamfer plane is a lightweight, compact, safe, healthy, cost efficient, environmentally sustainable and pleasant tool for quickly cutting chamfers in wood without leaving ugly ripples or burn marks on the wood, or ruining our hearing, or filling our lungs with sawdust. I couldn’t work without mine.
If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.
Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or or the IT manager for HRC’s bathroom server farm, and so won’t sell, share, or profitably “misplace” your information. If I lie may all my chamfers chip and become slivers in my fundament
Like to the fleeting world of ours, Methinks, are the frail cherry-flowers, For they that bloomed yesterday Are seen to-day to fade away.
Anonymous
It’s cherry blossom season in Japan.
Your humble servant works hard to keep this website focused on tools, as promised, and strives to not pad it with vain and pointless pictures of pets, projects, or product promotions. But every 4 years or so I like to add a post about cherry blossoms, that beautiful flower so important to the people of this island nation.
These photos are mostly of cherry trees and their blossoms in Tokyo proper, a metropolitan area of a little more than 14 million residents containing approximately 13,400 km2 (5,190 sq mi). But despite the difficulty and cost of maintaining them, Tokyo’s residents love their cherry trees adorned in white and pink dresses, and look forward to visiting and admiring them for a few days every year. This is an old and worthy tradition indeed.
I don’t pretend to know much about flowers, but I love trees. So I am posting this in tribute to the adornment of the cherry tree, for like all things that live, their petals will be glorious for only a few days, then fail. Can any of us hope for finer raiment or a more glorious future?
YMHOS
An old cherry tree in a nearby park. Its trunk and limbs are dark and twisted, but its flowers are lovely as ever.The same old cherry tree dancing into the sky. Fallen petals are scattered by the wind to decorate the ground for a brief time.A family has setup a picnic under the cherry tree. I think Treebeard would praise this treeA row of cherry trees with people enjoying the flowers and a picnic lunchThis old cherry tree is nearing the end of its flowers, but it has turned the asphalt below into a pink carpet.Even the house across the street, wet with rain, is adorned with petals.Mrs. YMHOS in her cherry blossom pink best.
Everything in life is risk, from the minute you wake up in the morning and stick your tongue into a toaster.
Anon
Introduction
In this article your most humble and obedient servant will present an obscure fact about traditional Japanese handsaws I call the “Mystery of the Burnt Blade,” as well as a related psychedelic conundrum called “Black Light!”
I will also provide a brief description of how one of the last sawsmiths in the world hand-forges his custom handsaws, and explain how these two mysteries are linked to this ancient, even magical, process.
If you have a metallurgical psychologist’s hat, as I do, perhaps one made of aluminum foil, or better yet, brass with attached wires, bells or baubles, now is the time to secure it to your “seat of knowledge.”
In a world boiling-over with mysteries, however, prioritizing them is sometimes vexingly difficult. For example, is the “Meaning of Life” more important than “Were Bert and Ernie in Love?” Or is the question “When will the Entwives return from shopping at the mall?” weightier than “Are the four surviving Nazgul running just Shat Fransisco or all of Calipornia?”
Cogitating such mysteries has worn my thinking cap down to just a button and a bit of lint, but before I forget (I’m supposed to take some bitter little green pills for my memory, but keep forgetting) I would like to address the subject of this article. As mysteries go, it’s nowhere near as high on the priority list as the whereabouts of the Nazgul’s missing PAC funds, but nonetheless it still puzzles many. Being exceptionally perspicacious, Gentle Reader may find a worthwhile gem or two hidden among the rubble.
And the story goes something like this.
The Story
The curtain on this mystery doesn’t open on a moonless night, black and ragged as a Chicago politician’s soul, concealing a MacBethan circle of wart-covered witches chanting incantations while stirring a cauldron bubbling over purple flames.
Nor is the scene of this mystery a locked cell in a curiously vacated wing of Gotham’s Metropolitan Correctional Center where the guardsmen all nap cherubically, security cameras have all malfunctioned magically (perhaps due to a “Nox” spell?), and where a millionaire child nookie bookie has shuffled off his mortal coil by hanging himself with a bedsheet after breaking his own neck. Harry Houdini must be proud!
No, the curtain on this mystery opens of an early evening in Tokyo almost 40 years ago in front of a rickety old wooden building facing a busy street erected in the warm ashes produced by 174 B-29s on the nights of March 9th and 10th 1945 when the city and many souls burned brightly.
Gentle Reader, we find ourselves in front of the shop and residence of a small, pipe-smoking saw sharpener and his family. They live on its second floor, with a workshop on the ground floor adjoining a dirt-floored doma with a single rickety sliding door opening to the street. There’s space in the poorly lighted entry for perhaps three people who don’t despise each other to stand, but no more. The shop space doesn’t have shelves or glass cases, just teetering stacks of newspapers and magazines wrapped in twine crowding in from the walls permeated by the perfume of oil and steel filings. I don’t know about you, but it’s an atmosphere I love.
Prior to that time my experience with Japanese handsaws was limited to inexpensive hardware store products with bright shiny blades. I didn’t know much about who made them or how they were made, but they seemed to work OK. On the day of this mystery I was looking for a more specialized saw for ripping 6X6 timbers, one not sold by the average hardware store, so I visited the shop of this professional saw sharpener.
As I opened the rickety wood and glass sliding door and called a greeting the little saw sharpener came out from the back, kneeled seiza-style on the raised floor of his workspace, and smiled like a wood carving of a buddhist saint.
After introductions, I described the job I needed to do, the type of wood I had to cut, and the type of saw I thought would work best. He made a thoughtful face as he sorted through his stock of saws in his mind, bobbed his head decisively once, stood up, and without saying a word went into the back. He returned with a saw blade wrapped in newspaper.
When I unwrapped the blade (no handle) my heart sang as I gazed upon its unadorned, elegant lines and subtle beauty. I could feel the blade quivering with excitement at the prospect of being fed some yummy wood after a boring confinement in the back of the shop. It was a 300mm single-edged kataba rip saw with the brand “Nakaya Genji” hand-chiseled into the steel blade.
The saw sharpener told me it was made in Tokyo (yes there were still many sawsmiths living and working in Tokyo back then) by a reputable and skilled blacksmith, but not a famous one, that it was a hand-forged, top-quality working tool, one he had sharpened himself, and that he thought it would satisfy my requirements.
The only problem was cost, about thrice what I had budgeted, but pretending I knew what I was doing, I flexed the blade, held it up to the dim light to check the plate for untoward distortions, and the teeth for cavities. I even pressed my palm against them to check their sharpness. After all this posturing I agreed with the saw sharpener that it was a fine blade. With one reservation….
Mysterious Colors
A hozohiki rip saw hand-forged many years ago by Takijiro for your YMHOS
Now, at the time of my visit to the little saw sharpener’s curious shop I didn’t have enough experience or specialized knowledge to ask intelligent questions about the steel and techniques used to forge and tooth the saw, but although I was ignorant, my eyeballs were still not “fushiana” (“knot holes 節穴”), as the saying goes in Japanese, for they noticed something that wasn’t quite right.
What was this smudge on the saw’s face that shocked me but did not faze a professional saw sharpener? It was a localized discoloration at the center of the blade, a vaguely-shaped area golden brown in color, possibly indicative of the blade having been exposed to high temperatures, perhaps hot enough to soften the steel, a serious defect indeed in the case of chisel and plane blades.
The saw sharpener was not impressed in the least with my knothole’s perception, but exercising extreme patience, gave me a partial explanation.
As he clarified at the time, and as I was able to confirm in more detail during the intervening years, this area of color is commonly seen on the plates of quality saws made in Eastern Japan, which included Tokyo where I purchased the saw in question, but it is not commonly seen on saws made in Western Japan, which have simple bright steel blades instead. Likewise, inexpensive, mass-produced handsaws, including exchangeable-blade kaeba saws, never have this colorization. Ahah! The thot plickened.
C&S Tools’ hozohiki rip saw hand-forged by Nakaya Takijiro. Please notice the colorization.C&S Tools’ dozuki crosscut saw hand-forged by Nakaya Takijiro. Please notice the colorization.
So what I deduced from his comment was that this spot of color is neither strange nor suspicious, but is actually desirable, indeed seen as an indicator of quality, depending upon geography. Sound hinky to you? It did to me too.
An Historical Example
Years ago the following example was related to me by a reliable source with personal knowledge, and I while I am extremely fond of daring fashion statements, I have not seen it with my own knotholes and so won’t accept any bets about its veracity that involve a forfeit of wearing lady’s underwear on my head out in public again, so please don’t offer.
From 1639 to 1834 Japan was closed to foreign countries with the sole exception of Holland, and even then access was severely limited.
In the early 1800’s a Dutch doctor purchased a bunch of Japanese woodworking tools which he took back to Holland. Those tools recently returned to Japan and observers noted they had the same appearance as modern handsaws saws made in Eastern Japan, evidence that this colorization is not just a modern feature of Japanese handsaws.
How to Make a Traditional Japanese Handsaw
In order to explain the metallurgical roots of the Mystery of the Burnt Blade I humbly beg Gentle Reader’s kind indulgence as I relate the following summary of the process of making a hand-forged professional-grade handsaw in Eastern Japan as explained to me by Nakaya Takijiro Masayoshi, one for the few remaining master sawsmiths in the world. Any errors are the sole responsibility of your humble servant.
Takijiro posing in front of his forge.Takijiro applying a final polish to your humble servants bukkiri gagari saw. Two of his anvils are visible. Please notice the scraper marks and colorization of the blade
Steel Selection
Saw blades do not require high levels of carbon. Indeed, too much will make the teeth fragile. Shirogami Saw steel and Shirogami No.2 steel have been popular for many years, and Takijiro uses S-2, but he prefers Yellow Paper steel with its lower amount of carbon for the extra toughness it affords.
With materials now in hand, let’s get to smithing.
Cutting the Plate
The sawsmith first cuts the steel plates for a run of saws using manual shears. These are not embroidery shears held in one hand, but rather a hand-powered single-bladed mechanism operated while sitting on the floor.
Initial Forging
Using a gas/charcoal forge, springhammer, hand hammers, and rectangular steel anvil he then heats and shapes the plates.
At the conclusion of this stage the saw plate is an approximately saw shaped piece of thin steel, burnt in appearance and warped. The iron tang will be attached later by forge-welding.
Nakaya Takijiro forging a saw tangNakaya Takijiro’s forge set into the floor of his smithy.
Annealing/Normalization
The next step is to annealthe saw plate. Sometimes this process is called “normalizing.” While it involves heating and cooling the blade, instead of making the steel hard, it makes it as soft as possible.
The purpose of this step is to relieve stresses, create a uniform and relaxed crystalline structure in the steel, and to soften the steel to prevent cracking during forging.
Annealing and normalization are very similar processes, both performed by heating the steel to a specific “recrystallization” temperature”(about 750˚C or 1380˚F for Shirogami No. 2), and allowing it to “soak” at that temperature for a specific amount of time. In the case of annealing, steel is left in an oven while temperature is slowly reduced in accordance with a specific heat curve. But when performing normalization, the white-hot steel is removed from the forge/oven and allowed to cool at room temperature, a faster, more economical process.
The traditional Japanese annealing/normalization process Takijiro employs at this stage is technically not pure annealing, but neither is it simple normalization. He heats the blades and upon removing them from the forge immediately places them to soak and slowly cool overnight inside a sealed, but neither airtight nor temperature-controlled, container filled with rice straw ashes, a low-oxygen, high-carbon atmosphere.
This annealing/normalization process is hot and dirty work, unsuited to either impatient factory workers or to mass-production, one that it adds considerable time and cost to production while yielding few benefits purchasers nowadays can discern using Mark-1 Eyeball, as seen through the lens of what I call “Chinese Logic.“
Why Chinese logic, you say? Because the benefits it imparts to the crystalline structure of a steel blade are not only impossible to analyze without using an expensive SEM, but are difficult to check through conventional non-destructive quality control procedures, and impossible to judge from an illustration in a catalog (harking back to the Sears Catalog days) or a digital photo on the internet, all reasons why this critical step is always neglected by other than well-trained, dedicated craftsmen like the blacksmiths C&S Tools works with, who refuse to cut corners.
The next morning, the blades are removed from their resting place in the ash box. At this point they are still too hot to handle without gloves or tongs.
Cold-forging
Now that the saw plates are roughly shaped and annealed, the next step is to further refine their crystalline structure by forging them using hammer, tongs and anvil. Takijiro does not, however, heat the blades during this step.
During this stage Takijiro prefers to forge blades by hammer and hand two at a time, one stacked on top of the other. The position of the blades in the stack is changed frequently so approximately the same number of blows directly strike both faces of both blades. Not only does this save time, but it cushions and better distributes the force of the hammer blows.
He then repeats this process by hammering both sides of a single blade.
The purpose of all this violence is to “tighten up” (shimeru 締める) and improve the blade’s crystalline structure, the primary benefit of “hand-forging” tools and weapons. This is not possible in a mass-production situation.
Obviously, if this step is performed carelessly, or by untrained factory workers and without properly annealing beforehand, a blade will crack sure as eggses is eggses. Just another of those jobs not suited to the amateur.
Quenching
The purpose of quenching the blade, of course, is to create a rigid, hard, even brittle crystalline structure.
Quenching Step 1: Heat the blade in a gas/charcoal fire to 800 degrees beginning at the blade’s tang end.
Quenching Step 2: When the blade is properly heated, plunge it it into rapeseed oil (canola oil is genetically-modified rapeseed oil) cooling it quickly. For more details, please read The Story of a few Steels.
Forge-weld the Tang to the Blade
The next task is to attach the soft iron tang to the hard steel blade by lapping the tang over the blade, heating the lap, and hammering until the two pieces meld. This technique, called “forge welding,” is as old as blacksmithing but has not been standard practice in Japan for the past three or four decades having been entirely replaced by electrical welding.
Takijiro does not use a welder.
Performance-wise, a forge-welded tang is not superior to an electrically welded one, but since it’s a sure sign of a hand-forged sawblade and indicative of traditional craftsmanship, it’s a detail highly desired by those who know the difference.
A forge-welded tang identified by the curved line crossing the blade just above the “machi” step-down to the tang.
Tempering the Blade
Quenching makes the blade hard, but also brittle and quite useless as-is. The purpose of tempering therefore is to slightly break-down steel’s crystalline structure while reducing the amount of carbides, thereby making the blade flexible and much tougher.
Proper tempering also greatly improves a blade’s edge-retention performance. This is a key step in the Mystery of Steel, and in the case of Takijiro’s handsaws, is accomplished in four steps.
Tempering Step 1: Heat the blade to 300 °C (570˚F) beginning at the toe (tip) end of the blade, allowing the temperature increase to spread to the tang.
Tempering Step 2: Place the blade on the floor to air-cool.
Tempering Step 3: Reheat the blade to 400˚C (750˚F) beginning at the tang end of the blade, allowing the temperature increase to spread to the toe end.
Tempering Step 4: Place the blade on the floor to air-cool.
The portion of the blade near the forge-welded tang needs to be left a little softer for toughness and to allow the blacksmith to chisel his signature, one reason for the two-step process.
Removing Warpage from the Blade
Subjecting a thin piece of high-carbon steel to extreme violence by fire, hammer, and sudden cooling in oil during the operations described above will always make it warp, so it must next be straightened by the precise use of hammer, tongs and anvil. This is a task that requires patience and much experience. Once again, a task impractical if not impossible in a mass-production situation.
Adjusting the Thickness and Taper of the Blade.
Two customer ryouba saws, one made in Tokyo and the other Niigata, with handmade handles of larch wood. The colorization is especially dramatic, and although the blacksmiths are different, the color is nearly identical.
The faces of a true high-quality hand-forged saw blade are not tapered willy nilly, nor in the simple parallel planes typical of mass-produced ground-and-sanded blades. Instead it must be shaped in a “double-taper.” In the case of a kataba (single-edge) saw, the first taper is from the teeth to the blade’s back, meaning the blade is thickest at the teeth, becoming gradually thinner towards the back.
The second taper is the blade becoming thinner from tang to toe.
Combining these two tapers results not in the creation of two flat planes in the saw blade, but curved surfaces on both faces of the sawblade. Please make sure you understand this detail well.
Let’s examine this double-tapered surface in a bit more detail. A case in point is the more complicated double-edged ryouba saw. If we examine a cross-sectional cut across a high-quality ryouba sawblade’s width (perpendicular to the long axis of the blade), we will observe that the blade is thinnest at its long center axis and thickens moving outwards towards the teeth on both sides so that, as the blade cuts deeper into the wood, the gap between the blade and hairy sides of the cut increases.
If we next examine a cross-sectional cut through the length of the blade, we will see the plate is thickest at the tang-end and thinnest at the toe, such that as the blade is pulled towards the user, the portion of the blade cutting the kerf is always thinner than the kerf itself, thereby reducing friction and the tendency to bind and buckle. The combination of these two tapers on each face of a sawblade is what your humble servant calls a “double taper.”
Restating the previous paragraph, as result of this double-taper the thickness of the sawblade inside the kerf being cut measurably decreases as a stroke progresses, incrementally reducing the pinching forces acting on the blade in the kerf, as well as the friction of hairy wood fibers on the blade. The net result is that the energy necessary to motivate the blade is decreased, cutting precision is improved, and the blade is less likely to be damaged by buckling.
In the case of double-edged ryouba saws, this increase in thickness from the plate’s centerline to the teeth has limited usefulness, however, because, as the blade cuts into the wood deeper than its centerline, the blade gradually becomes thicker increasing friction in the kerf. This is one reason why some craftsmen, including your humble servant, prefer single-edged “kataba” saws over the more cost-effective and convenient ryouba saw.
These pinching/ friction forces can also be reduced, of course, by adding extra set to the teeth. But set is not all blue bunnies and fairy farts because, while it’s indeed effective at reducing pinching/friction forces acting on the blade in the direction of the blade’s width, it is not effective in the direction of the blade’s length, unless a large amount of set is added.
Applying minimal set matters because the greater the set, the more wood must be cut, the more time and energy must be expended, and the more cutting precision is reduced. Cheap saws and replaceable-blade saws lacking taper must have a humongous amount of applied set, BTW, an ungainly and wasteful feature despised by knowledgeable craftsmen.
A high-quality handsaw with a good double-taper will cut with less effort, in less time, without binding, and with greater control and precision than a plain, flat saw, even one with adequate set. Contingent, of course, on the skills and perception of the user.
I don’t know where this subtle idea was first developed, but I understand it has been used by advanced blacksmiths throughout the world for centuries. Why? because it works.
So how does the sawsmith impart double taper to a blade? It begins with having a vision of the finished blade in-mind when shaping and forging the blade with fire, hammer and tongs. But there are practical limits to the precision achievable with fire and hammer, so the master sawsmith will adjust the blade’s thickness using two-handed scrapers to shave steel from the plate.
Takijiro’s toolrack of two-handed sen scrapers.A pile of hardened steel shavings from a saw plate produced by Takijiro’s sen scrapers.
Although few know them and even fewer use them nowadays, scrapers were once tools found in every metal working shop around the world. In trained hands they are capable of achieving amazing precision, such that all metalworkers and even college students studying machinery engineering in the USA as late as the 1960’s were trained extensively in their use.
Expensive 3-axis CNC grinders can do the job, but conventional grinding and sanding equipment is unable to achieve the quality of taper that hand-scraping can.
The marks hand scrapers leave on a sawblade are obvious and very different from those left by grinders and sanders, and being the results of handwork, are something to look for when evaluating a saw. On the other hand, ground, sanded and polished blades are shinier and prettier than scraped blades, and if the polishing was done after tapering by hand with a scraper, I can find no fault with it.
But please be aware that extensive sanding and polishing contribute nothing to a saw’s performance, while on the other hand are highly effective at concealing grinding failures. More sizzle less bacon.
Caveat emptor baby.
Cut the Teeth
The sawsmith uses a hand-powered shear contraption with tooth-shaped blades (kinda sorta like the teeth in pinking shears) to cut (or punch) the teeth. The teeth produced during this step are quite rough.
Rough Filing
The sawsmith uses hand files to shape and refine the teeth cut in the previous step.
This first filing operation produces properly-shaped but not perfectly sharpened teeth.
Applying Set
Now that the teeth are properly shaped, the sawsmith applies right-left set to the teeth using an anvil and a special hammer. The following videos YouTube videos show the process, although at a much slower pace than real life.
The next step in the process is for the sawsmith to use a hammer, anvil and chisel to carve his legal, registered signature into the blade just above the tang, as seen in the photos in this article. This feature was perhaps borrowed from the sword world, but no one knows. In any case, it’s this unique signature and the way it was cut that witnesses the handmade nature of the saw as well as the name of the craftsman that made it.
Sometimes this brand name is easily read, but often the characters are stylized to the point of illegibility. For instance, not only your humble servant, but most Japanese are unable to read even one of the six characters in Takijiro’s signature. “The signature is the signature” he explains.
Sharpening
With the teeth shaped and set applied, the teeth are now ready for their final sharpening.
Traditionally, most blacksmiths simplify this step to a quick and dirty sharpening, but for an extra fee, they would send the blade to a professional sharpener for a more refined sharpening job called “Honmetate” (hohn/meh/tah/teh 本目立て). Takijiro, however, was trained by his master to a higher level of proficiency, and for the first 3 years of his apprenticeship was tasked with sharpening saws exclusively, skills that are wonderfully obvious in the performance of his saws. All of his saws receive honmetate by him.
I was unable to find a video showing a professional sharpening job on a cabinet-grade saw in-action, only jobs on larger saws, mostly for trimming apple trees. But while the tools and process are much the same, the skill and speed required to sharpen the numerous fine teeth of a dozuki crosscut saw are awe-inspiring.
The Answer to the Mystery of the Burnt Blade: Coloration (Irozuke 色付け)
In the Japanese language this final step in the saw making process is called “irozuke” (ee/ro/zoo/keh 色付け) which I’ve translated as “colorization.” In the Japanese language this translates directly to “apply color.” It’s also called kesho ( keh/sho) 化粧), which is the same word used for makeup, as in the gunk and powdered pigments women and actors apply to their faces.
In this step, the sawsmith uses a deformed truncated cone, simply a piece of sheet metal bent into a cone with the pointy end cut off and smashed into an oval shape.
He places the wide end of this cone in his forge, or on a gas stove, so the heat will rise and be funneled into an oval shape. He rests the sawblade on the narrower, upper end of the cone so it focuses heat onto a specific area of the blade. When the blade reaches the right temperature, as judged by color changes, he removes the blade and allows it to air-cool.
The answer to the Mystery of the Burnt Blade, therefore, is this “colorization.”
As described above, the first time your humble dogsbody saw a professional-grade handsaw in Tokyo I was shocked at the sight of the golden-brown spot of color on its blade. Since then, I’ve heard many suppositions for its existence, most pungent BS, but the true reasons for this additional step are threefold.
Colorization is the final step in the tempering process, one that slightly softens the steel in a critical spot to make the blade tougher. This is one application of “differential hardening” a technique of which blacksmiths are extremely fond, one that is important to a saw’s performance.
Second, the resulting differential hardness slightly reduces the blade’s springiness by damping the tendency in a thin hardened-steel plate to develop resonant harmonic vibration, a problem that inflicts many saws. Gentle Reader may have experienced this while using large Western panel saws when the blade tends to vibrate and quickly “waggle” right and left towards the end of the return stroke, movement that is not only distracting but wastes time and can harm precision. This characteristic too is important to those with the skills adequate to tell the difference.
And last, at least in Eastern Japan, colorization is clear evidence that the saw was properly forged without taking any shortcuts, much like an actress will take care in applying her makeup before a performance, except that, unlike bottle and powder makeup, colorization on a sawblade reveals instead of conceals. Oh yes, and it costs a hell of a lot less than Gucci Beauty‘s foundation gunk.
Theatrical makeup tastefully applied to a lady performer at the Beijing Opera. Were a trowel and sandpaper involved or just Photoshop?Colorization applied to a Japanese Kabuki actor. Obviously a different kind of theater.
The Black Light Mystery
I will conclude by relating another mystery about handsaws Master Nakaya Takijiro shared with me
According to Takijiro, scraping a sawblade by hand can reveal the quality of the forging and heat-treatment of a saw blade in ways no other methodology can, because shavings freshly scraped from an expertly-forged and heat-treated blade will, for a brief moment, exhibit a shiny black color, what he calls “black light” (kurobikari 黒光). On the other hand, shavings scraped from an inferior blade will always be plain bright steel.
A grinder is unable to provide this quality insight.
Conclusion
Despite the subject of this article being somewhat obscure, I pray it has has been informative.
Until we meet again, I have the honor to remain,
YMHOS
A cherry blossom lake in Shakujikoen Park in Tokyo
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Introduction
This is the second in a two part series about Japanese exchangeable-blades handsaws (“kaeba saws”).
In Part 1 we examined the history of how these saws came to be, how they are manufactured, and the market forces that made them so popular in Japan and even overseas. In this conclusion we will consider their advantages and disadvantages compared to traditional fixed-blade saws, and explain a few simple techniques Gentle Reader can employ to improve the performance of one variety.
I think all who have used them will agree that exchangeable-blade handsaws (“kaeba saws”) are effective and convenient products. However, Gentle Reader may be pondering, no doubt with exquisite grace and dignity, the question: “Do kaeba handsaws exhibit performance superior to well-made traditional handsaws?” The simple answer is unequivocal: sometimes yes, sometimes no. The Okey Dokey list below summarizes the reasons supporting your humble servant’s decisive answer.
But to avoid too much confusion, let’s briefly review the materials and techniques used in making the kaeba handsaw before attempting to navigate Okey & Dokey.
Review of Materials and Production
You will recall from Part 1 that kaeba saw blades are manufactured in automated CNC production lines using pre-hardened, pre-sanded, sheet steel of uniform thickness purchased from rolling mills. The sawmaker’s machinery cuts out the blade blanks, deburrs them, punches the teeth, shapes and polishes them with automated precision grinders, adds set to the teeth, and sometimes tensions the blades between rollers. The teeth of some blades are also instantaneously induction heat-treated (what some manufacturers call “impulse hardened) producing teeth harder than a sawfile.
Unlike the blades of traditional, high-quality saws, however, kaeba saw blades are not differentially hardened, taper-ground, trued or hammer-tensioned, nor are their teeth professionally sharpened, tuned or quality inspected. And of course, the backs of backsaws like dozuki are not carefully fitted. These are big, decisive differences not apparent to the untrained eye.
So with these physical differences in mind, let us next consider the pros and cons.
The Okey Dokey List
Some Advantages of Kaeba Handsaws Compared to Traditional Handsaws
Lower Initial Cost: The initial cost of kaeba saws is less than traditional hand-forged saws. This is to be expected as they are mass-produced on automated machinery involving zero handwork by craftsmen.
Greater Convenience: Dull or damaged blades can be quickly replaced with new, sharp blades improving convenience and obviating the need to carry entire bulky spare saws, and to have their teeth resharpened.
Greater Durability: Kaeba sawblades with induction-hardened teeth (aka impulse-hardened teeth) are more durable and remain sharper longer than traditional fixed-blade handsaws, especially when cutting EWP (engineered wood products) such as plywood, MDF, OSB, LVL, glulams, etc. which contain hard adhesives and abrasive sandpaper grit. This is not the case for all kaeba sawblades, of course. From the craftsman’s viewpoint, this is perhaps their most significant performance advantage, and is nothing to sneeze at.
Disposable: Like cat litter, plastic beverage bottles, and modern marriage, kaeba saws are a “use and toss” product that need not be repaired, only replaced. Fortunately, unlike marriage and cat depositions, lawyers don’t get involved much.
Disadvantages of Kaeba Handsaws Compared to Traditional Handsaws
Less Economical Long-term: While cheaper when new, and although some kaeba saw blades can be resharpened (except those with induction-hardened teeth), the cost of a new replacement blade is typically more expensive than the direct cost of a professional sharpening job, another profit motive for planned obsolescence
Limited Blade & Tooth Options: While popular blade and tooth shapes/quantities are readily available, the specialist blade shapes/teeth required for woodworking trades and tasks other than carpentry (e.g. luthier, fine interior joinery, kumiko zaiku, large rip and crosscut work, smooth cutting of hard woods, etc.) are simply not available as kaeba saws often leaving craftsmen who rely solely on kaeba saws bereft of adequate tools. Case in point: most kaeba saw blades are designed to cut the varieties of softwood commonly used in housing construction quickly and efficiently but are not well suited to cutting most hardwoods smoothly or precisely. On the other hand, some craftsmen and certainly professional saw sharpeners can readily modify the teeth of a traditional saw to satisfy specific job requirements. Younger craftsmen that grew up using only kaeba saws do not even realize this sad state of affairs. I encourage Gentle Reader to learn how to sharpen your own noble saws.
Unknown Materials & Quality: As mentioned above, kaeba saw blades are made from pre-hardened, pre-sanded sheet steel (chemical content undisclosed) of uniform thickness supplied by rolling mills (nation of origin undisclosed). When your humble servant first inspected a kaeba saw maker’s plant around 2010, they were using high-quality, clearly-identifiable steel of known chemical composition produced by a reputable Swedish mill (specs and QC marks etched on the surface of the steel), but now that kaeba sawmakers have effectively conquered the handsaw market in Japan, the “bait and switch” principles taught by Harvard Business School and exemplified by McDonalds hamburglers have been fully implemented. Not unlike BS, B&S is an extremely profitable business management tool, one considered wise by some short-sighted business executives and those who can’t count past 20 without dropping their pants. Caveat emptor, my dear.
Differential Heat Treatment: Although some Gentle Readers may be unaware of the importance of differential heat treatment in an excellent sawblade, much less the pros and cons thereof, kaeba sawblades lack the advantages of the differentially hardened plate found in quality, traditional Japanese (and Western) handsaws resulting in:
Decreased toughness of the plate
Increased springiness and resonant vibration in-use often harming precision;
Taper Grinding: Being made of uniform-thickness sheet steel, the kaeba sawblade is not taper-ground resulting in:
Increased binding and kinking in use. A kinked sawblade, of course, is irritating and destroys precision. It’s also less than worthless because it interrupts the user’s work as he replaces it, an inconvenience and expense the uninformed user typically blames on himself even though the true culprit is the inferior sawblade.
Greater set is required to avoid binding and kinking, which equates to more energy and time expended to create more sawdust, a positive factor for weight loss, but not so much for efficient work.
Greater tendency of the blade to wander in the cut increasing irritation while reducing precision.
Sketchy/No Hammer Tensioning: Although some kaeba blades are tensioned between steel rollers in the same way circular sawblades are, the tensioned area in kaeba saws is a band across the length of the blade, and not the ideal oval shape sawsmiths typically produce by hand resulting in greater susceptibility to warpage/buckling as the blade heats up in use resulting in increased friction in the cut, reduced work efficiency, increased irritation to the user, and more damaged blades requiring replacement thereby increasing the profits of sawblade manufacturers, distributors and retailers. Another of Baldrick’s cunning plans?
Less Precision: The precision achievable using kaeba backsaws such as dozuki is significantly less than that of high-quality hand-forged traditional dozuki backsaws for the following reasons:
The back may not be straight;
The back is not secured to the blade as securely permitting more slop;
The plate has never been trued and may not track as precisely.
The set of kaeba saw blades is decidedly excessive for precise joinery work.
Rougher Cuts: Kaeba blades typically have greater set compared to traditional sawblades necessitated by their lack of taper grinding, making the saw cut less smoothly. In addition, uneven left-right set often encourages the sawcut to wander into the weeds.
Landfill Stuffing: As mentioned in Advantage 4 above, like cat litter, plastic beverage bottles, and modern marriage, kaeba saws, are “use and toss” products, veritable landfill stuffing in-waiting. I will leave it to Gentle Reader to decide if this is good or not, but I am convinced kaeba saws find the transition from valued tool to rubbish lonely and emotionally damaging, which explains the increased demand for board certified metallurgical psychologists such as ton modeste serviteur.
Only Gentle Reader can answer the question of which type of saw is superior, but despite my sometimes negative observations listed above, I freely admit to liking and using both types in the context of “horses for courses.”
User Improvements to the Kaeba Dozuki Saw
Many moons ago I associated with a group of young, energetic and extremely pragmatic carpenters in Tokyo intent on finding solutions to deficiencies in modern tools anyone could put into effect. For instance, one item they studied to death was how to get the most from synthetic waterstones, a highly-successful bit of research IMHO.
Another tool they researched was the kaeba dozuki. While they didn’t propose any new, earth-shattering innovations, some of their techniques are worth employing.
Improvement No. 1: Side-jointing the Teeth
This first tuning technique is one that works on all handsaws and can especially help your kaeba dozuki saw cut straighter and more precisely, leaving a narrower kerf and smoother surfaces. This is traditionally performed using a file in the case of standard sawblades, but in the case of a kaeba dozuki saw with induction-hardened teeth, we need to use a harder tool and with more precision; Enter the Arkansas stone stage right.
You will need a new kaeba dozuki blade, a hard (not soft), flat Arkansas whetstone (novaculite) dimensioned approximately 8″x3″ (larger is OK but much smaller won’t work well), a piece of white copy paper, a can of light-weight spray lube such as WD-40, CRC5-56 (not PTFE), or brake cleaner, a relatively clean toothbrush, and a clean cotton rag. Please note that India stones, carborundum stones, waterstones, diamond plates won’t get the job done.
Lay the paper down on a flat, stable, wooden board or workbench. Place the sawblade on top.
Give the blade a light spray of lube.
Gingerly place the hard Arkansas stone lengthwise on the blade parallel to the cutting edge, with one end hanging approximately 25mm (1″) off the toe end of the blade, one long edge resting on the blade, and the opposite long edge hanging off the blade about 6mm (1/4″) past teeth.
Without placing any downward pressure on the stone, pull it towards the heel (handle end) of the blade, parallel to the tooth line, in a single smooth stroke until the end of the stone is hanging about 6mm off the heel of the blade. Slow or fast, it makes no difference, but I prefer slow. Just one stroke, mind you. The goal is for the stone to lightly abrade the sides of the tips of the teeth essentially “jointing” and bringing them all into line. In addition, and perhaps more importantly, even if your sawblade has perfectly uniform teeth, kaeba dozuki blades almost always have too much set, which this technique will reduce, improving the smoothness and precision of the cuts it makes.
Turn the sawblade over and repeat steps 1~4. With this the stone will have made a single pass over both sides of the tips of all the blade’s teeth. In the case of blades with induction-hardened teeth, you may need to make 2 passes of the stone per side, but be aware that every pass reduces the useful life of the blade significantly. Also (and this is very important if you value your sanity), be sure to make the same number of strokes in the same manner to both sides of the blade.
Take the blade outside and blast it with your can of spray lube to remove any particles of stone and metal left in the teeth. You may not be able to see this swarth (mixture of stone, steel and lube residue), but it is there, and if not removed, it will dull the blade during the first stroke in wood sure as eggses is eggses.
Use the toothbrush and more spray lube to scrub the teeth to remove any remaining swarth residue.
Spray the blade with lube or brake cleaner from both sides with the teeth pointing downward flushing any remaining swarth out of the teeth.
Wipe the blade with the cotton rag from the blade’s back over its teeth. You don’t want the teeth to cut the cloth, or the cloth to catch on the teeth. If you observe any swarth residue on the cloth, repeat steps 6, 7 & 8. Do not use the saw until all the swarth is gone.
Tasting the Pudding
Now that the sawblade’s teeth have been side jointed, let’s test them to see if they need further persuasion.
You’ll need a piece of flat, knot-free softwood like pine with one straight/square edge, perhaps 150mm (6″) wide and 19mm (3/4″) thick. Use your marking knife and hardened square to mark a line on the wide face perpendicular to the straight edge. Clamp this board to your supporting bench or sawhorse with the line you just made hanging off the side.
With the saw’s edge angled about 30˚from the horizontal plane (surface of the board), begin a cut from the far end of the line. use a light touch and let the saw cut where it wants to cut. Does the saw cut a straight line, or does it tend to wander to the left or right?
You may not be able to tell from this initial test, but pay attention when using the saw to see if it tends to wander from the line. If it does, the teeth on the side of the blade it tends to drift towards may have too much set, in which case use the same stone and lube to joint the teeth on the offending side. Be very gentle because there’s a risk of making it worse.
Again, be aware that side jointing the teeth means you will have to joint the top of the teeth more than usual next time you sharpen them reducing their length and the overall lifespan of the blade that much more. This is not a big loss for kaeba saws, but will reduce their lifespan.
Improvement No. 2: Tuning The Back
Straightening a kinked and/or twisty saw can be a little like wrestling the carp in the wood block print above. I don’t know the story depicted here, but I’m pretty sure it’s a scene in a kabuki play. The guy in middle with the sword is an actor named Onoe Tamizo playing a carpenter named Rokusa. The guy on the right with the ugly scowl is played by Banto Hikosaburo (no sword visible). The lady (?) on the right with the short sword is played by Onoe Eizaburo. These are all male names because men play the female roles in kabuki plays, and acting troupes then were often related as they are now.
Dozuki saws have steel backs used to stabilize the thin blade and protect it from buckling. In the traditional saw this is a folded strip of steel that clamps over and tightly grips the back of the blade, much like Western backsaws. In the case of kaeba dozuki saws, however, the back cannot tightly grip the blade too tightly or it will be impossible to replace the blade, reducing the money, money, money, money, mo-ney the manufacturer needs Gentle Reader to contribute towards his purchase of that new Italian sportscar and the Greek vacation he promised two of his girlfriends (at the same time?).
The problem is that this necessary “tolerance” (aka “slop”) often allows the blade to wander more than is necessary. But what to do? I propose three useful techniques below for Gentle Reader’s kind consideration.
Deburring the Slot
The first item we need to check for is burrs inside the slot in the back. This is not a frequent problem, but it does occur.
Begin by removing the blade from handle/back, reversing it, inserting the nose or tail of the blade in the slot, and without cutting your hand, running it back and forth in the slot. This should give you a good idea if there any big burrs or restrictions in the slot. If you find any, mark the location on the back with a marking pen.
Next, and while it may imperil your extravagant income and glamorous lifestyle as an international hand model, run your fingernail inside the slot checking for burrs that might tend to tweak the blade this way and that.
If you detect any burrs, a skinny deburring tool might get rid of them. Be careful that bits of metal don’t fall inside the slot.
Or, you can fold a piece of wet/dry sandpaper (220 grit?) in half and run it back and forth in the slot where the burrs are hiding removing/smoothing them. Some of that spray lube might help. When doing this, once again be careful to prevent large pieces of metal from falling inside the slot. When done, thoroughly flush out any swarth and bits of metal with a few squirts from your can of spray lube or brake cleaner while swinging the handle like a helicopter rotor blade. I guarantee The Mistress of the Blue Horizons will neither understand the importance of this manly ritual nor appreciate the artistic spots it may leave on her walls and ceilings, so I suggest you perform it outside, with style and grace of course.
Straighten the Back
With the slot safely deburred, let’s next consider the back’s straightness. Obviously, if a saw’s back isn’t straight, the blade won’t be either, and the cut it makes will tend to wander. So you need to check the back, and if you determine it’s out of wack, correct it.
The back, being made of folded sheet metal, is not a precision-milled component, so please don’t expect perfection, and firmly quash any OCD persnicketiness.
With the blade installed, use a precision straightedge held against the sides of the back with a lightsource to check for bow and gaps. Be sure to check both sides. A steel straightedge like that of a combination square will work, but a thinnish beveled-edge straightedge like our 400mm stainless steel straightedge by Matsui Precision works best.
A feeler gauge may be helpful in evaluating any gaps.
Straightening the back is not something readily done with a hammer for a number of reasons, but we can bend it straight if we are careful. To do this, lay the saw, with blade attached (this is important), on a flat workbench top or board with the cupped surface facing up. Place a stick of wood under and perpendicular to the back at the lowest point of the cup. The thickness of this stick is key and will take some trial and error.
Place one hand pressing down on the end of the back where it joins the handle, and the other hand on the far end. Press down slowly and carefully, bending the back without taking it past the yield point where the back will permanently bend. The back should rebound when you remove pressure, returning to its original shape without permanent deflection. Repeat this until you develop a sense of the pressure required to reach, but not exceed, the “plastic limit” of the back. You may need to add to the thickness of the stick used to spring the back.
When you have a good sense of the pressure required to just reach the plastic limit, press down on the back again with a little bit of extra pressure causing the back to permanently bend just a tiny bit. No pro-wrestling moves, please. Check the back with your straightedge to determine any improvement in straightness.
The same bending action can be achieved by placing the back, with blade attached to keep the slot from closing up, in a vise with padded jaws. Don’t clamp the saw in the vise tightly, but leave a little gap, and press on the back where it joins the handle, not the handle itself. This technique works well, but since it’s a bit more difficult to feel the plastic deformation of the back, and to control the point of flexure, it requires more self control. Please keep that darned inner badger under tight control.
If the back is snaking this way and that (very unusual), you can try the same technique in various directions.
Check progress with your beveled straightedge frequently.
If this doesn’t work, and your dozuki still refuses to make high-precision cuts, bite the bullet and replace it.
Tuning the Slot
Now that the blade slot is deburred and the back is fairly true, the next step is to determine if we need to improve the gripping pressure of the back on the blade.
This is a difficult job because we need the back to apply enough pressure on the blade to hold it in place without wiggling, but too much pressure will make it difficult to remove and replace the blade without damaging it. So begin by checking the fit of the blade in its slot.
Insert the blade and, while holding it under a strong light, push it right and left paying attention to any gaps that may open between blade and back.
If you discover any significant gaps, mark the locations on the back with a marking pen. A feeler gauge may be helpful. You will need to judge if the blade wiggle caused by these gaps is enough to warrant an attempt to close the gaps.
There are two ways to close any gaps; Both are risky. The first is to use a small hammer to tap tap tap on the back. The second is to use a vise or a C clamp to close the slot. Either way, be sure the blade is in the slot when you execute.
This concludes our tome about handsaw history, advanced business management techniques, rodent cuisine and modern marriage. I hope you found it informative.
YMHOS
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Joe Abercrombie, Best Served Cold
Introduction
Gentle Readers are probably familiar with the modern mass-produced mass-marketed exchangeable-blade handsaws made in Japan. In this first part of a two part series we will briefly examine the history of how these saws came to be, how they are manufactured, and the market forces that made them so popular in Japan and even overseas.
In Part 2, to be published later, your most humble and obedient servant will list pros and cons and share some techniques for improving their performance.
Gentle Reader may already be aware of these saws and even own and use them at work daily, but in this article your humble servant will share details about them not available elsewhere. I pray it proves informative, or at least entertaining.
Terminology
In the Japanese language the type of consumer-grade handsaw I mentioned above with blades that can be removed and reattached to a handle mechanism are called “kaeba nokogiri” (kah/eh/bah nokogiri 替刃鋸) meaning, of course, “exchangeable-blade saw.” From this point forward I will call them “kaeba saws” for brevity. They have entirely replaced traditional forged handsaws in Japan for good and valid reasons, and indeed are popular throughout Asia as well as Western countries too.
So let’s begin this adventure by considering the history of this new version of an old tool that shook the handsaw world like a terrier does a rat.
Historical Background
In the late 1970’s the kaeba handsaw appeared in the Japanese market changing everything.
I’m not sure who first developed the concept, but there’s no doubt it was inspired by the convenient and highly-profitable bits and blades used with powertools. The first automated equipment for making these sawblades was developed by a 150 year old company located in Sanjo, Japan that shifted their traditional saw sharpening business to producing and selling CNC saw sharpening machines. Later, inspired by automated circular-saw blade production techniques, they went on to develop CNC machinery to fabricate handsaw blades in an automated production line.
Production Methods
The manufacturing process begins with materials, of course. The primary material is pre-hardened sheet steel sanded to uniform thickness in rolling mills, and delivered to the blade manufacturer in large, heavy rolls. This product means the blade manufacturer doesn’t have to sort, forge, heat-treat, stress-relieve, or taper-grind the steel. In fact, he couldn’t even if he wanted to.
As this roll of sheet steel is unspooled into the production line, CNC machines cut and deburr the blade blanks, punch the teeth, and shape and sharpen them with special abrasives, after which set is applied by machine. And unlike traditional hand-forged fixed-blade saws, the plates are not forged, taper-ground or heat treated by the saw manufacturer at all. This is an important distinction to those who know saws from shinola.
Some but by no means all such blades are tensioned between two steel rollers in imitation of the techniques used during the manufacture of circular saw blades.
Most kaeba manufacturers induction-harden just the tips of the teeth of some blades for extra durability as the blades are fed between, and instantaneously heated red hot by, electrically-charged copper blocks, then immediately quenched in coolant spray after exiting the induction blocks leaving them a darker oxidized color. These blades cannot be sharpened by hand as the teeth are harder than files.
Handles
Kaeba saw’s handles are sometimes made of wood, sometimes of plastic, and sometimes of rubber over plastic. The blade is secured to the handle by metal mechanical widgets and sometimes screws integral to the handle. The blades can be quickly and easily changed encouraging consumers to do so frequently, but each manufacturer’s blades will fit only their proprietary handle locking the consumer into buying proprietary replacement blades, much like printers and ink/toner cartridges, because as the O’Jays sang on Soul Train, it’s the blade that makes the money, money, money, money, mo-ney, but it’s the handle that drives market share.
And with labor costs to produce such a handsaw a single digit percentage of what’s required for a traditional handsaw, the few manufacturers of kaeba saws find it difficult betimes to wade through the mountains of mad stacks laying about.
With the production technology perfected, compatible materials available, and CNC machinery in the hands of a few manufacturers, it was only a hop skip and a jump to widespread sales of kaeba handsaws, and if I may paraphrase my old carpenter foreman Uglúk, it looks like rats are back on the menu, boys.
Some prefer their rodent roasted on rye with horseradish sauce, but I prefer mine sauteed with a drop o’ Tabasco Sauce, or as Bert suggested, maybe even a floater for delicately piquant flavor! What about you?
The Societal Impacts of Kaeba Handsaws 替刃鋸の波及
I mentioned above that this new type of saw changed everything. Of course, that’s a bit of an exaggeration because babies still love boobies and politicians graft, but indeed some things changed drastically in Japan.
The first big change the kaeba handsaw wrought was putting nearly all the traditional sawsmiths in Japan out of work in a matter of a few decades. Indeed, the number of sawsmiths still forging traditional saws full-time nowadays can be numbered on the fingers of one hand after a manicure using a tablesaw.
The second domino was the near destruction of the saw handle industry. As the demand for exchangeable-blade handsaws ramped up, the production of traditional handsaws, along with the need for traditional handles, crashed.
You see, exchangeable-blade saws have patented brand-specific wooden handles with integral metal mounting plates/screws/clips to which the specific blade-maker’s replacement blade is attached. The maker of each brand of exchangeable-blade handsaw subcontracts the production of their handle to specific suppliers, and since the producers of handsaws are now few, so are the handle suppliers. Sadly, your humble servant is aware of only one, and occasionally two producers of traditional handles still operating. I believe they still have all their fingers but I’m concerned one gentleman’s liver has seen better days.
Just when it looked like things couldn’t get worse, the third domino fell-over and crushed the saw sharpening trade. While many kaeba saws can be resharpened, some cannot be economically resharpened at all because their teeth are induction-heat-treated to be harder than sawfiles. In fact, while it’s usually a little cheaper to have even a kaeba sawblade professionally sharpened rather than purchasing a replacement, buying a new sawblade and tossing the old one is quicker, more convenient and obviates the need to carry spare saws to a jobsite because thin, lightweight replacement sawblades will suffice. In any case the jobs of saw sharpeners (metateshi meh/tah/teh/she 目立て師), like those of sawsmiths, handlemakers, wheelwrights, and honest climate scientists have been practically eliminated.
The one overarching societal lesson one can take away from this is that technological advances always have and always will engender painful changes in every industry in the world, and the case of the Japanese handsaw industry only confirms that one can either ride the train of technology sipping tea and eating pringles in comfort as it rolls along, or grease the tracks as it runs one over. Just ask the once mighty Eastman Kodak company of camera and film fame if ‘taint so.
A similar progression occurred within the saw manufacturing industry in the West, but instead of the changes stemming from product innovation, the causes were quality adulteration, active neglect of customers needs, and abandonment of unparalled tradition. Welcome to the Harvard School of Business Management’s model of “profit through disruption” in action. I hear they’re looking for a new university president.
An American Handsaw Maker
To this point we’ve taken a shallow look at Japanese handsaws, especially the impact of the kaeba variety on Japanese markets, but highly intelligent Gentle Readers (could there possibly be any other kind? absolutely not!) may wonder how in heck these strange Japanese products managed to make such profound inroads into Western markets, so a few points about a well-known American saw manufacturer may prove instructive.
Gentle Reader may recall that the famous American handsaw manufacturer Henry Disston (1819–1878) was born in England the son of a designer and manufacturer of lace-making machines and immigrated to the USA in 1833 along with his father and sister. His father died three days after stepping off the boat. Tough luck.
Being a determined and diligent young man, Henry apprenticed himself to a saw company in Philadelphia, Pennsylvania. In 1840 he went independent, and after some lean years building a reputation for quality, he founded the Keystone Saw Works there in 1850. After the American civil war his son Hamilton joined the business and Henry changed the company’s name to Disston & Son, and later to Disston & Sons. At its peak Disston & Sons was the largest and most productive saw manufacturer in the world with 8,000 direct employees working on 300 acres.
At the time he established the Keystone Saw Works, nearly all tool steel used in North America was imported from Great Britain. This was a serious impediment to growth so Henry established the first crucible steel mill of consequence in the Americas to supply steel for his products and to support the war effort, and although other more famous, ruthless individuals falsely took credit for developing steel production in America, they were originally only Henry’s customers. For the next 25 years, the Disstons were among the largest producers of quality tool steel in the world outside England.
Interestingly, American consumers at the time were absolutely convinced that only Birmingham, England could make quality tool steel, so while other American sawmakers imported their steel from England, D&S used their own steel, avoiding the high import tariffs of the time. But to avoid the stigma of being seen as a “colonial product,” for many decades the acid-etched engraving on Disston & Sons’ sawblades included variations of the words “London Spring Steel” intimating that more prestigious British steel was used. Interestingly modern chemical analysis suggests that D&S’s tool steel was at least as high-quality as that imported from Britain at the time.
The first handsaw I owned as a young man was an antique and terribly rusty D&S D-8 thumbhole rip saw missing a handle (but with partial screws) I found languishing in a joint compound bucket in the back of a Las Vegas pawnshop. My penny-pinching carpenter father said it could be restored to be a better saw than I could buy new, and at $3 and a lot of elbow grease, the price was right and so was he. After derusting the blade, making a handle from a piece of scrap walnut, and reworking the teeth several times until I got the nack, that antique D-8 became an excellent handsaw, far superior to the new Disston saws still available at the time. My son owns it now.
A classic 28″ Disston D-8 swayback rip saw with a 2 hand thumbhole stock. Not my rescue saw but close.
The first point I want to make in this section is that by the time I was old enough to want to own a handsaw, the circular saw ruled the construction industry in the West (but not yet in Japan) and most younger carpenters neither owned a decent handsaw nor could care less. As a result of these market changes, the production and sale of handsaws became less profitable, the quality of those available became shamefully degraded, and instead of increasing production efficiency, and/or innovating like Japanese saw companies did, D&S did a double doodoo on quality, then lay down to be eaten by vultures. Other than a few tiny, recently-established boutique backsaw makers, the once-mighty American handsaw industry is now as dead as decency.
My second point is that this shameful degradation and subsequent abandonment of a once huge and profitable American industry fomented despair among Western woodworkers who needed quality handsaws but couldn’t procure them new anymore forcing many, like your humble servant, to haunt flea markets, pawnshops, and later Ebay for old handsaws (including Disston & Sons products) and to even purchase tools imported from Japan back when Japan’s reputation for quality was not as shiny as it is now. These forsaken and “disrupted” woodworkers, hungry for better tools, were the primary reason medium-quality but very sharp Japanese crosscut handsaws first became so popular in the USA. And when Japanese kaeba saws became available later, overseas markets snapped them up like the proverbial duck on a June bug.
FYI, the Disstonian Institute website has some interesting information about Disston & Sons those interested in history may enjoy.
As an aside, I noticed that Disston, now the Chinese holesaw maker, is offering a newer version of the D-8 26″ swayback rip/crosscut handsaw exclusively on Amazon. It looks shiny! The country of manufacture and local content is not listed anywhere, but probably not the USA and definitely not Philly. The video on their website almost made your unworthy servant spew chunky chunks. Consider yourself warned.
Let us next shift our attention back to the kaeba saw and consider the first and most popular such handsaw, as well as some other popular varieties.
Dozuki Kaeba Handsaw
The dozuki handsaw was the first Japanese kaeba saw to become popular overseas, perhaps initially attracting attention because it vaguely resembles the petite “gents” back saws once popular with amateurs. The dozuki is a thin crosscut backsaw (a single-edged handsaw with a steel or brass stiffener attached to its back) that cuts on the pull stroke.
The name is pronounced dough/zoo/key and is comprised of two Chinese characters: “胴” pronounced “dough” meaning “trunk” as in the trunk of a tree or the human torso, and 付き pronounced “zookey,” a verb meaning “to attach or make.” To the best of your humble servant’s understanding most Western woodworkers are unaware of the name’s meaning or the saw’s specialized purpose but nonetheless they use them for everything but spreading jam on toast (marmalade gums up the teeth terribly). The name refers to the job of cross-cutting the shoulders of tenons, but not the cheeks, which is a job for the specialized “ hozohiki” rip saw.
A 210mm dozuki crosscut saw with fine teeth for precision work. The manufacturer calls it a “kumiko” saw after the narrow slats found in traditional decorative joinery such as shoji and ranma. The teeth are not induction hardened. The fit between back and blade is pretty darn good and it makes excellent cuts, but the teeth have too much set for the highest-quality work.
In the case of joinery, furniture, cabinetry, and fine architectural woodwork, well-made mortise and tenon joints are essential to the appearance and even the strength of the finished product. And since the shoulder is the only visible part of most mortise and tenon joints, shoulder appearance is important.
Cutting tenon shoulders in a craftsman-like manner in the Japanese tradition demands not only a good eye, a good saw, and a skilled hand but speed, because the craftsman is expected to saw deftly, precisely and cleanly to the layout line the first time every time, all day long. This differs from the inefficient, amateurish methodology for cutting tenons in cabinetry and joinery as taught by the Holy Masters of Woodworking in the West who lack adequate saws and/or skills and shamefully advocate cutting wide of the layout line and sneaking up on it with chisels and planes. How embarrassing.
A quality dozuki saw is extremely effective at making these cuts. To do so it must be able to make a straight, precise, smooth cut right to a final layout line every time without wandering off into the weeds and without having to use a paring chisel or shoulder plane to obtain a clean, square, straight shoulder. Accordingly, it must have a thin, true plate that won’t produce excess friction, nor buckle, oil-can, or bind as it heats up, and fine, uniform teeth with minimum practical set. It must also have a lightweight but rigid steel back that effectively keeps the blade’s plate true, protects it from buckling, and discourages it from weedy adventures.
Kaeba dozuki saws come in various lengths ranging from 150mm to 240mm. TPI varies with maker. Zetsaw by Okada Industries is my favorite kaeba brand and makes some with induction-hardened teeth that can be made extremely useful with the modifications I will share in Part 2. FYI, your humble servant does not sell Z-saws and has never received free (or even discounted) samples, nor been wined, dined laid or paid to promote them.
Interestingly, even before the development of the exchangeable-blade kaeba saw, the Japanese dozuki saw was used in the West for cutting dovetails, a job which requires occasional crosscuts but frequent rip cuts, something the hozohiki saw does much better. In any case, that Western woodworkers ended up preferring the Japanese dozuki saw for even rip cuts may give Gentle Reader an idea about the comparatively adulterated performance of readily-available Western dovetail saws from the 1970’s onward.
The kaeba concept has been expanded to include useful saws of many shapes and sizes, some of which your humble servant owns and uses, especially when there is a risk of damaging one of his professional-grade fixed-blade handsaws.
Let’s next consider some popular varieties of kaeba saws other than the dozuki and hozohiki.
Kaeba Crosscut/Rip Saws
The best selling Japanese handsaw both domestically and internationally is the standard single-edged (“kataba”) carpenter’s crosscut saw. These come in various lengths, shapes, and with various types of teeth. They are handy in the shop, and I always have one or two of these on hand when working in the field, especially when cutting EWP (engineered wood products) which I refuse to allow my hand-forged saws to even touch no matter how much they wiggle and whine. If you need to cut plywood or other EWP, these saws are a must-have IMHO. More on this subject in Part 2.
A 265mm kataba crosscut saw with hardened teeth by Zeton owned by your humble servant. The blade has seen a lot of abuse and neglect. It has a paulownia wood handle still wrapped in plastic with the pricetag still attached.A 7sun (210mm) crosscut saw by Zeton missing a couple of its induction-hardened teeth. It has a soft paulownia wood handle that has seen better days. Hinoki would have been a better wood in this case.
But the usefulness of kaeba saws is not limited to woodworking and sandwich making only, oh no. I carry a 333mm (13″) kaeba formwork saw with a lightweight plastic pistol-grip handle when hunting because no other tool I know of is so light, so compact, and can cut so much wood so quickly.
A special-use kaeba saw I am fond of, with two of its blades shown. The handle (a Zeton product) is made of fairly lightweight but tough plastic, but its most valuable feature IMO is its short length which makes it fit nicely inside toolbags and backpacks. The 300mm blade, handle, and a wooden scabbard I made to fit, goes in the toolbag I take to jobsites. I have a plastic scabbard for the 333mm saw which I strap to my backpack when camping and hunting. Much lighter and more compact than an axe.
The Silky brand arborist’s saw blades are excellent for this purpose too if you ditch the heavy rubber handle and gaudy scabbard.
Ryouba Double-edged Kaeba Saws
This style of kaeba saw combines a rip saw and a crosscut saw in one exchangeable blade. I own one 270mm kaeba ryouba saw with induction-hardened teeth I like well enough, but I still prefer fixed-blade ryouba saws. I daresay most people can’t tell the difference.
A 270mm ryouba double-edged saw with hardened teeth by Fujiwara intended for interior installation work. The blade retention bar can be seen projecting from the center line of the handle. I’m unsure if this saw is still being producedThe same 270mm ryouba saw disassembled showing handle, blade, and wire retention clip. The two bent tabs at the end of the sprung retention bar fit into the two slots in the blade when assembled.The same 270mm ryouba kaeba saw showing the wire retention clip used to secure the two tabs that lock the blade in-place. Notice the blue-black discoloration of the sawteeth tips typical of induction-hardening.
Saws retailers here in Tokyo tell me that sales of kaeba ryouba saws have dropped off dramatically the last few years probably due to increased prefabrication and LGS metal studs replacing wood and LVL (laminated veneer lumber) framing for interiors such that rip cuts in wood in the field are seldom necessary. I believe this increase in the use of pre-manufactured components is in part due to three inter-related factors: (1) Rising construction costs; and (2) High demand in the construction industry; and (3) An aging workforce resulting in a decrease in available manpower in the construction industry making it difficult to meet customer demand. I fear the current attitude of Japanese women about bearing and raising children will prove disastrous for the nation soon as you can say “Bob’s not your uncle.”
Teflon Coated Blades
Zetsaw sells some of its blades with a PTFE teflon coating which I have found to be very effective in reducing friction and preventing sap from accumulating when cutting some softwoods. Makes a great egg turner too.
An 8sun (235mm) rip saw with hardened teeth and teflon coating by Zeton. This is an exceptionally useful saw.
The Adventure Continues
In the next installment in this operatic series about the funky love of money, fine dining and handsaws we will examine the advantages and disadvantages of kaeba saws compared to traditional fixed-blade saws, and explain simple techniques Gentle Reader can employ to supercharge your kaeba saws.
But in the meantime, since the IMF, EU and UN are on the verge of outlawing backyard vegetable gardens at the same time they are taking by force and sacrificing the land of European farmers on the alter of the religion of “Climate Change,” (how did that work out for Sri Lanka?) all while increasing pressure on others (regular people, but not the bureaucrats/elite) to substitute bugs for meat (I kid thee not), I would appreciate Gentle Reader sharing any tasty recipes you may have for crispy, crunchy low-fat rodent dishes in the comments below. I need to broaden my culinary repertoire in preparation for more societal “disruption,” you see.
YMHOS
I ain’t gonna eat no bugs!
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A Huon Pine, native only to the Island of Tasmania
Serit arbores quae alteri seculo prosint – “He that plants trees labours for future generations.”
Caecilius Statius, quoted by Cicero. Motto of John Quincy Adams and his family, among others
This is a guest post by Dr. Antone Martinho-Truswell regarding a highly unusual tree, his adventures working its wood, and his thoughts about permanence. Enjoy.
What Does It Mean to Build Permanence?
Woodworkers – and especially we odder, curmudgeonly, hand tool woodworkers – have a vexed relationship with permanence.
On the one hand, spend any time reading, listening, or talking to a woodworker of any integrity (not least our distinguished host, Mr. Covington), and you will inevitably hear about building things that last, creating furniture or structures that will outlive the creator. Or else you might hear lamentation of the impermanent, throw-away culture represented by particle board, OSB, melamine, wire nails, and so forth and so on. Stan writes regularly here about building for future generations, about tool chests that preserve and workshop stools that endure. When we chop a mortice or fit a dovetail, the idea is that the end product is permanent – the strength and durability of the outcome justifying the labour-intensive process of creating it
And yet: wood. We are not stonemasons. We are not goldsmiths. We work with a biological material, one subject to biological processes such as mold, rot, borers, gnawing things, weather, sunlight, fire and friction which eat and wear away at wood until it’s gone. Japan’s venerable old wooden structures, record holders across all human construction efforts, pale in age compared to those made of stone. Wood perishes as do all living things (at least since Valinor was sundered from the sphere of the Earth).
This is the story of a permanent wood. A wood as magnificent as it is rare, a wood that is itself a lesson in permanence, and my attempts to make beautiful things for now and the future.
Old and Young Places
I like to think about old things. I was born and grew up in Southern California, where almost everything is new, even the old things. I remember as a child a small water tower near my elementary school, proudly fronted by a sign announcing that it was the oldest building in the area – an august 25 years old. The tower is older now and so am I, but there were old trees around even then. Up north, there are sequoias and redwoods, and of course, the oldest of all, bristlecone pines. I was young then, and didn’t think too much about wood or lumber, but I knew the trees were old.
As a young man, I moved to England for graduate school, and the world was much older. There was a sense of permanence, in the material things at least: old buildings and old furniture and old books and old wood. Oaken chapel pews and blanket chests and linenfold panelling – the sorts of adornments that, in the USA, are the enviable preserve of grand old institutions in grand old East coast cities, but in the UK, found in all manner of great and humble places. But the trees weren’t so old. England’s ‘green and pleasant land’ is green with farms and fens, but not so much old forest anymore. Like much of Europe, over aeons humans have harvested so much timber that little old-growth forest remains, only secondary growth, coppices and managed woodland. The trees in England are fairly young because the culture is relatively old. I was not yet a woodworker, and I did’nt think much on trees and timber at the time, but I knew the culture was old.
As a married man, I moved to Australia, and here I remain. The prevailing culture – that of the settlers rather than the indigenous people of Australia – is young, and so are the trees. Mostly.
Australia’s frequent natural fires mean that most of the trees that grow here are adapted to grow fast and big, but not long. Generations of forest turn over quickly – in ecological terms that is – with bushfires killing off adult trees and causing their scattered seeds to germinate and grow a generation of newer, younger trees. What’s more, as in America, the brash, youthful settler culture did not have a good track record as stewards of the natural gifts of the island continent, and the few old hardwood forests that once existed have been over-exploited.
Perhaps with age comes wisdom, but now I am both a father and a woodworker, and I ponder permanence, and wood, a great deal, and what all this youthful forest means for woodworking here in the sunburnt country.
Hard, Stringy Wood
If you know anything about Australian woods, you know they have a well-deserved reputation for being really, really hard.
The vast majority of our forests and the trees that grow in them are the various and many species of eucalyptus and its near relatives, with two qualities that make them a mixed blessing to woodworkers.
First, they are fast growing, so as to quickly repopulate the land after fire, and second, they are extremely hard – the softest commercially available eucalyptus wood is called “Victorian Ash” (or “Tasmanian Oak” – same wood, different source) in the timber trade with a hardness similar to white oak or rock maple. The hardness of other varieties can easily range up into ipe and ebony territory.
Rainbow Eucalyptus
The result is an abundance of eucalyptus wood great for things like flooring and fenceposts, but fast growth makes it especially stringy, which together with phenomenal hardness makes it difficult to work with handtools. That same Victorian ash, the most common of all hardwoods in commercial use here, is among the best behaved, and a straight grained piece can take a nice glassy finish from a hand-plane, but we have nothing commonly available with the smooth texture of a maple or beech. Victorian ash works like oak at best. The other good furniture eucalypt is Jarrah, which is a lovely orange-brown colour and less splintery than most, but it’s expensive and a good bit harder than maple, so still a challenge. Moreover, it comes from Western Australia, which, along with Victoria, banned all native forestry at the start of 2024, so it is likely to recede to only niche use in the future.
There are many other beautiful, softer, easier working, and often fragrant Australian hardwoods, but for one reason or another all of them are scarce and hard to track down.
There are few species under plantation production here, and the fast-growing eucalypts crowd out most other species in our forests, so the best cabinetry timbers, like acacias and mahogany relatives, are rare. If you find these timbers for sale, it’s usually from a small-time operation that harvested a fallen tree – so you have to wait around for luck to smile on you. I try to snap up Australian Rosewood priced reasonably. The vast tracts of cabinet timber we once had – the famed Australian Red Cedar, which is actually a mahogany cousin, for example – were all irresponsibly exploited down to commercial extinction decades ago. A permanent culture of wood use requires a forestry industry with an eye toward permanence, which we didn’t have for a long time, and many argue we still don’t – hence the aforementioned bans and the limited selection of commercial wood.
A few government agencies and private companies are trying to improve sustainable forestry in Australia focusing on Australian blackwood (Acacia melanoxylon). This species should not be confused with the African blackwood of oboe, clarinet and bagpipe fame. Australian blackwood is a dead ringer for Hawaiian koa, and is its closest living relative. It has a rich, deep, brown colour with the same gleaming chatoyancy of koa, but its name comes not from the colour of the seasoned wood, but rather the black color the sap turns sawyers’ hands.
It’s a breathtaking timber deserving of widespread admiration, and one of the few beautiful cabinet timbers down here that weren’t over-exploited to near extinction in the last century. The blackwood timber industry is apparently a bit wiser than their forebears, and so harvests less and charges more to promote sustainability. It’s the nicest timber that can be bought here straightforwardly, and is priced accordingly.
The Ships that Took Our Trees
Clipper Ship, City of Adelaide, 1000 tons
Of particular interest to users of Japanese tools and Japanese woodworking methods and mindsets are softwoods, and this is where Australia is confusing. There are no true pines native to any part of the Southern Hemisphere – but settlers insisted on naming all the fascinating and unusual softwoods down here “pines” – and then importing a northern hemisphere species for most of our plantation wood.
Norfolk Island Pine
Norfolk Island Pine
When Britain established the first penal colony at Sydney in 1787, the site was chosen partly because it was thought to offer a good strategic back-up to the British claims on Norfolk Island – a speck 900 miles out into the Pacific. The trees covering this island – Norfolk Island pines – were thought to be particularly valuable to the Royal Navy, as they tended to produce ramrod-straight single trunks, almost as if replacement masts had been conjured up from the Earth. However, the timber proved too flexible for masts, and the idea was abandoned, though the Norfolk pines got their second act as a popular ornamental plant (including a few all the way back in my home town in California).
Hoop Pine
Much more useful is hoop pine, a near cousin of the norfolk pine that grows on the Australian mainland, and is our only plantation-grown native conifer. I’ve made shoji from hoop pine; it has nice straight grain producing a good shine when hand-planed. The only other commercially available native softwood is Australian white cypress which has a beautiful smell and is famously insect resistant, but unlike most softwoods it’s harder than American oaks. It also doesn’t grow very big, so is mostly used for knotty, sapwood-sapwood edged fence posts, or equally knotty floorboards and decking. I understand that it is not a sustainably managed species, and conservationists often recommend against its use.
Monterey Pine
The Australian construction industry relies on plantation grown monterey pine (also called radiata or pinus radiata) for all of its general purpose lumber. This is an import from California, now very rare in its natural habitat but grown all over the Southern Hemisphere to compensate for a dearth of native pine species. It is a particular pet-hate of Australian woodworkers, in online forums and general conversation, who lament its often crumbly texture and poor strength. I don’t hate it though – it can take a lovely plane finish and the wide grain does make for beautiful patterns on clear, flat sawn boards.
Huon Pine
Like all Australian trees, huon pine is misnamed. It isn’t a pine at all but rather the only member of its genus – more akin to a cypress than anything else, yet still not a cypress, a thing of its own.
Fans of Tolkien’s works may lament that its name is Huon and not Huorn, but no tree was ever more deserving of association with Tolkien’s tree-herding Ents, that ancient race of sentient defenders of the forest.
Huon pines grow only in Tasmania, and only in the wet and mountainous western regions protected from fires. Provided they have that protection, they may achieve something most Australian trees do not – great age. Huon pines grow incredibly slowly, barely thickening as century after century wash over them, living at least 2000-3000 years, with some thought to be even older. This is best evidenced in the astonishing tightness of their annual growth rings. It is not uncommon to see specimens with annual growth less than half a millimetre – or to put it another way, the trees gain less than two inches of trunk radius per century. While immensely slow, these trees can still grow immensely large when given that precious critical thing – time. They are probably the longest-lived trees in the Southern hemisphere, and certainly in Australia.
There are lots of small huon pines growing now, though few big ones. They should be huge, but they are not, because the great ones were all mostly cut down to build boats – a vast fleet of huon pine watercraft were constructed in Tasmania, using up most of the big trees. The promise of the perfect tree for shipbuilding that had fallen flat on Norfolk Island paid off big time in Tasmania with the huon pine. The reason for the single-minded use of these ancient trees for shipbuilding will become obvious, but as a result of this hasty zeal, they are now the single most protected species of tree in Australia, both to allow the forest, with Ent-like patience, to recover, and to preserve the few very old and very large specimens that remain.
Beyond the Grey Rain-curtain
These trees are old, though their lives are but the beginning, and death, as Gandalf once taught young Peregrin Took before a fateful battle, is just another path beyond which the journey does not end. This is, cynically, true of all wood that gets put to human purpose, but it is true in a special way for huon pines because of a unique chemical in their wood. Not unlike other fragrant cypress-like softwoods – including Japanese hinoki – huon pines contain great amounts of oil, in this case, an oil called methyl eugenol that protects them from insects and other wood-hungry nasties. Methyl eugenol is, as it happens, the ticket to eternity for wood.
For whatever reason, methyl eugenol, in the very high concentrations in which it is found in huon pine, is astonishingly successful at preserving timber. Huon pine timber is highly prized for shipbuilding because it’s easy to bend and work, completely impervious to insects and fungus, and readily survives the rigors of the aquatic environment. All that ever seems to happen to huon pine is that the surface turns grey in the sun – much like teak. And then it simply endures.
And I mean it endures. The 3,000-year age of living huon pines is one thing, but researchers have found fallen huon pine logs on the floor of the forest that have lain there, unmolested by decay, for as much as 38,000 years! Not petrified, not fossilized, just oily wood under a weathered surface, simply enduring.
These characteristics are also why we still have a bit of precious huon pine timber available nowadays, reclaimed from time to time from old boats and old furniture, as durable and enduring as ever. Moreover, the foresight that was missing when the trees were mostly cut down a century ago was not blind when hydroelectric dams came to Tasmania. In the 1970s, with two valleys set to be flooded, the Tasmanian government allowed loggers to go into the valleys and cut down the pines – but not to take them. The loggers, working in tall boots even as the dam waters were rising, would leave the logs where they fell, to float up to the surface of the new lake as the waters rose.
That was 50 years ago – the logs are still there, floating on the lake. The outer layer turns grey to about 1-2mm in, and then, inside, the creamy golden wood, as perfect as the day it was felled, endures. The decades afloat harms it not at all, and every year a tiny portion is licensed to be taken for restoration and preservation jobs.
This is all the unreclaimed huon pine that there is or ever will be for woodworkers to use, and they estimate they have about 50 years’ worth left at current extraction rates. But with the wood so impervious and eternal, what is already in cabinets and drawers and tables and ships will continue to circulate and be reused. It is a wood with true permanence.
An Unexpected Responsibility
At this point I will enter the story to share the most harrowing and rewarding of my experiences as a woodworker.
By chance, I had the opportunity to acquire three large slabs of huon pine, cut and dried in ages past but never used. Compared to the tiny crafting boards and turning blanks that are generally available (at great price), this was a bit of a windfall. I could have, with all cynicism, listed each one for sale for several hundred dollars, pocketed the profits, and went on to buy more quotidian woods. I did not do this for two reasons.
First, and perhaps most pointedly, with visions of epoxy pours and hairpin legs plaguing my dreams, I was overcome with a sense of responsibility to “protect” this precious wood – whatever that means. I wish to acknowledge, in self-reflection and humility, that I am an amateur woodworker. A reasonably experienced and meticulous one – but an amateur nonetheless, albeit one who works with hand tools and has the hand tool mindset. My work is fine but not perfect. But I suppose I like to think that the tool marks I leave here and there, occasional tear-out, and other mistakes that remain have a certain honesty and worthiness to them, becoming of a slab of great age. Vanity of vanities, all is vanity…
More than that though, I saw in these slabs of huon pine, and in the legends of these trees, an opportunity for permanence. Here were three great hulking slabs of a tree older than the nation-state it was felled in (I counted 800 growth rings on one of the slabs – and it wasn’t even a centre slab), thick and strong, and made of the closest wood comes to being an imperishable material. Here was the opportunity, if it was ever going to exist, for a piece of furniture that might outlive the memory of my name.
It had to be a table. Only a table could use to best effect the wide expanses of precious wood – laying them out on full display for all who saw them to admire. No matter how perfectly I might make a cabinet or chest, it would not do justice to the material. And, as history, archaeology, and literature show, only a table is so intimately connected to life and family and holiness by its proximity to hungry mouths, little hands, and eager minds as they first do their colouring and then their maths homework, and then their college applications. Only a table is ever so truly loved by generations as to be worthy of wood older than all those generations combined. I simply couldn’t bear cutting the beautiful slabs into small pieces. So for months I fretted; and worried; and stressed about the crushing responsibility of making the first cuts.
The Weight of History
I am an apartment woodworker. My family home is a house in the mountains west of Sydney, but I work as Dean of a university college and we live most of the time in the Dean’s residence, an apartment on campus. I am blessed with a very patient and indulgent wife and an apartment that happens to have a sort of wide corridor I use as a tiny woodshop. Space is still limited, though, and I try not to stockpile wood (in the interest of stockpiling tools – ahem). So, three slabs, two metres long and the best part of a metre wide, mocked me each time I had to shuffle past them. And still, I fretted.
I eventually decided upon a refectory table so that no matter how many chairs are crammed around it, none clash with the legs. And with a strong stretcher tusk-tenoned into each leg to allow it to knock down, so that I could make it big but still fit it through doorways. Most importantly, I needed to keep the two 800mm wide boards that made the tabletop flat – so sliding dovetails across the bottom to counteract any cupping. And those sliding dovetails would be a perfect place to pin the top to the legs, with removable dowels, again so it could be knocked down to move. Drawbored mortise and tenon joints to hold the I-shaped legs together without glue (since all that wonderful oil makes gluing troublesome anyway). A kanna-shiage (handplane finished) top for beauty and touch, with just a light coat of oil and hard wax, so that the wood itself can be appreciated. A magnificent vision. Complex and well-chosen joinery. Perfection worthy of the tree. Entirely beyond my experience or skills…
I had to start by getting to know the wood. Before any cutting or marking or anything, I realized I could not confront the massive task I had set myself without first knowing what it was to get huon pine under saw and plane, to see, feel it, and smell it.
.
I hoisted one of the slabs onto my sawhorses, and with a few strokes of the little aogami roughing plane on the left, and a few more of the shirogami finishing plane on the right, I had my first look at the slab, and my first curls of huon pine shavings. (No, Stan, I don’t London finish my plane bodies. They are dirty, it’s patina.)
The smell – oh the smell. The smell of huon pine is unlike anything I have ever experienced. It is sweet and rich and almost creamy, but without even a hint of sugariness or caramel, nor any of the medicinal notes of cedars or cypress. I suppose the aroma is a little like gardenia flowers, but different. And it’s persistent. I saved bags of little offcuts that are no less fragrant now than a year ago.
The scent was such that I almost did not notice the figure at first. From some angles, nothing more than a very tightly grained, golden softwood, with rippling grain caused by the irregular growth of the tree’s surface over the centuries is visible. But when the light strikes the surface of the top at the right angle, a shimmering sea of lamellar rays cutting across the grain pop out, almost obscuring the grain with its gleam. Beautiful but subtle – much like the scent. This image and this aroma is now linked with permanence in my senses.
With the feel, smell and appearance of the wood now embedded in my mind I began to feel more confident about beginning my table project. One serious concern remained, however, namely: tear-out.
Layout That Fills the Workshop
I started in with trepidation, hoisting the two closest matched slabs onto my horses and getting to work. In my little shop, I have no room for a great big assembly table, so the slab was my workbench, and took up the whole shop. Here you can see my cramped little shop, replete with little atedai against the wall, assorted tat taped and hung on the walls (including my Palm Sunday palm, awaiting the coming Ash Wednesday), my tool chest brusquely stolen from Stan’s design, and a lovely old tansu filled with bric-a-brac.
Layout was painstaking, although not because the joinery was especially complex. Before shaping, the two “I” shaped legs were six simple boards and the stretcher would resemble nothing so much as a 2×4. The only complexity to the initial layout arose from the graceful radius I had planned for the long edges of the two top slabs. I could have cut them with straight edges and cut the curved edges later but that problem would have been unnecessarily wasteful.
One simply cannot waste this wood. If you have any respect or regard for the trees that support our craft, it repulses the conscience to even put plane shavings into shop bins. Moreover, I absolutely refused to cut these slabs in anything but the most efficient, offcut-preserving way. As a result, layout took days (or, rather, nights. Amateur, remember?).
The two surfaces of the slabs I used for the top each had unique flaws and virtues. In the end, curving the tabletop’s edges to accommodate the natural edges and features of the slabs proved effective in maximizing the tabletop’s size while minimizing waste of this rare and valuable wood. For example, in the photo above you can see where the near right corner of the slab narrows towards the end, an inconsistency my layout had to accommodate. This layout was also necessary because two of the slabs were contiguous in the bole and one was not, such that the two contiguous, matched slabs had to be used for the top even though one was somewhat larger than the other.
Dealing with the constraints that imposed this layout taught me important lessons in collaborating and compromising with the wood. In line with Japanese tradition, I knew I wanted the “outside” surface of the board to be oriented upwards in the table, and so my layout prioritized that side. As a result, both slabs ended up with prominent natural flaws on the underside – like greyed areas, bark incursions, and even one gash that looked as though the tree had been struck with a red hot poker.
There is a school of thought in modern, machine assisted, YouTube recorded woodworking that cannot tolerate such defects, no matter how small or natural, in any piece of furniture, demanding they be either removed entirely or filled with colored epoxy. The first approach I reject because wood is natural and I believe it should feel natural. I enjoy the fragrance of the wood, and the feel of running my hand along the underside of the table, sensing the evidence of the tree’s story, together with the tool marks I intentionally left. The latter approach I reject because epoxy is plastic, and I work with wood. The table bears the scars it earned in life, but only reveals them to those with enough appreciation and humility to get down on their hands and knees to gaze upon them.
Putting Blade to Wood
I do not now, and suspect I never will, own a table saw. Someday I might own a bandsaw, but I’m not convinced. In any case, I won’t have any of these things in the house whilst my daughters are young, as much to spare my family’s lungs from dust as to avoid injuries, however unlikely.
So that meant I had to figure out a way to accurately break down these slabs along my layout lines with hand saws, in a room that barely contained the slabs.
I couldn’t do it on the sawhorses – that would require me to stand on the slabs to make the long rip cuts, which seemed risky to their integrity without a supporting table underneath, especially when sawing the narrower pieces. And the slabs were too long and too heavy to comfortably use the Japanese low horse and foot-clamp method, which I am normally fond of for long rips.
The solution I selected was to support the slabs horizontally on one long edge using my 6-inch thick planing beam, with the other long edge supported on low horses with extra boards taped to them to make up the difference in height. This provided enough vertical clearance under the slab for a kataba saw. This arrangement had other advantages too. As I ripped from one end of the slab to the other, I could stand on the slab directly above the supporting planing beam, which was in turn resting on the floor, preventing the slab from shifting position while avoiding downward deflection of the ever-narrowing slabs.
My back did not love this hunched sawing position, but it was more comfortable than you might expect, and in two long sessions of rip-sawing, I had everything broken down to pieces: two wide top planks, each tapered on one edge, two vertical leg pieces, four feet and aprons for the I-shaped legs, and one long stretcher. As it happened (and as you can see below) the offcut from the third slab was almost a perfect extra stretcher. I still have it and will use it for something someday. It is the world’s most magnificent (and I suspect valuable) pine 2×4. The two venerable katabas, one rip and one crosscut, may be seen taking a well-deserved rest after rendering magnificent service.
With designing, planning, layout and rough cutting done the project shifted to the shaping and joining phase requiring greater attention, so I put down the camera, and did not pick it up again until the job was done. Sadly, I don’t have photos of gorgeous shavings rippling off planes, or of the massive Anaya-nomi I used to cut the mortises for the stretcher to pass through the legs, or of the nakin-kanna rounding off edges.
This work was more-or-less conventional furniture-making; taking the neatly rectangular pieces of wood I made in the rip-fest above and shaping them into components using good steel and keen eye. I didn’t follow a borrowed or historic pattern for any of this, but worked out my own take on the refectory style of dining table with two I-shaped legs and a single stretcher.
I made a pattern of a single asymmetric curve using a bit of sturdy brown paper shopping bag, leaving the carry handle attached to hang it on my shop wall throughout the process so it was always to hand. I used this same curved pattern throughout to define all the curves in the project, starting with the concave slope from the mortise in the feet to their toes, the tapers from centre to ends on the vertical legs, and again as the most important curve in the project – the gentle swell of the tabletop’s long edges from one end to the middle and then tapering back to the opposite end again.
Once the base was completed, the conventional woodworking ended and the real gauntlet began – the top.
The top was made with the two long, wide boards shown with my kataba saws in the photo above. At almost 400mm wide each, they were a challenge to handle, a bigger challenge to plane, and an even bigger challenge to keep flat.
The work of planing the wood went alright. The swirly grain of huon pine is not terribly prone to tearout, and like all quality softwoods, is a joy to plane in the direction to which it agrees, producing shimmery, breathtaking surfaces. The trouble is that each 400mm board contained 800 years of growth rings with grain direction changing within each board many times due to storms, cool summers, and a lightning strike or two as empires rose and fell. And with such tight grain an entire century of growth, along with the changes in the tree’s environment that impacted that growth, ended up recorded within a mere five centimetres of width – narrower than the thickness of a standard 70mm kanna – and often without apparent visual clues. As a result, seemingly neat, fine ribbons of shavings pulled end to end would be followed by tiny but significant tearout here and there across the board.
Reader, this took days – days of sharpening by very best white #1, fine mouthed, perfectly (amateur-perfect, mind you) tuned kanna. Days of shaving just exactly to this specific point, in just this direction, just so, to clear up a spot of tear out, then switching sides and going the other way, hoping and praying and watching that I didn’t overstep the boundary and have to start over – which I did, many times. And all the while, awkwardly walking around the massive slab, leaning over it to plane the far side, getting half up onto it like a billiards player, and then doing it all over again on the other slab. There is still some tear out in the surface, especially around the teardrop-shaped bark inclusion that gracefully adorns one corner of the tabletop. But it’s pretty close.
Keeping it Flat
An important aspect of the project was ensuring the wide, solid-wood tabletop remained permanently flat through changes in temperature, humidity, loading and coverings. In the case of such wide slabs, there was only one realistic solution – sliding dovetailed battens on the underside. This design detail had the advantage of providing two level, perpendicular surfaces to connect the legs to the tabletop.
Of course, a hard cross-grain connection between the battens and the tabletop using glue and screws would end in tears after just a few years, so I cut two blind sliding dovetail slots in each half of the tabletop beginning at centre joint of the toward to about 8-10cm of the edges, then cut dovetails into the battens to fit. The two planks hold the battens captive between them once installed, and the friction in the sliding dovetails locks the two slabs together without glue, dowels or hardware.
To use glue anywhere in this project seemed wrong. In any case, the oils in huon pine don’t play nicely with glue, and the joinery connections were the better plan.
I cut the dovetails in the battens and tabletop planks using my cleverest of all Japanese planes – the male and female dovetail plane, a rare beast indeed.
With the battens installed I cut 10cm wide shallow bevels on all four lower edges of the top, tapering the top to create the illusion of a tabletop only 20mm thick from a slab about 40mm thick in the centre. This involved a lot of plane work.
I left the underside a bit more rustic, even allowing large areas of “live” bark to remain as a lagniappe to the worshipful person who surveys the underside. You might think that leaving bark on the underside meant that I contravened the usual practice of Japanese woodworkers of using the outside surface of a plank as the show surface, but no – though not Japanese, I cleave to this principle invariably, but in this case, the history of the tree involved so many twists and turns that the bark inclusion was exposed on the inner surface of the board.
For clarity, allow me to explain what may not be obvious from the photos. The two legs are connected by mortise and tenon joints to horizontal feet at their lower ends and horizontal beams at their upper ends. In turn, the trestle leg beams are connected to the two battens by four dowels, two at each batten, that pass through the beams and battens at an upwards angle. After exiting the batten, the end of each dowel presses tightly against the underside of the tabletop, slightly bending and binding it in place.
To disassemble the table in preparation for relocating it to our home in the mountains outside Sydney, I just need to knock out these four dowels and slide the battens out of their dovetail slots, and knock out the two wedges in the ends of the tusk tenons securing the spreader beam connecting the legs. This design has worked well, and the dowels are strong enough that the table can be lifted and carried by the top alone.
The Finish
Now, a great part of me wanted to leave the wood unfinished, both to enjoy the raw kanna-shiage surface, and to ensure the magnificent smell would not be diminished. But, to provide some protection and give a bit of extra visibility to the lovely grain, I gave the wood a couple of coats of thinned pure natural tung oil, and then rubbed on and buffed out several coats of carnauba wax creating a surface hard enough to help protect the relatively soft wood from dings and scratches. Also, my wife liked the colour better oiled than unfinished, a very important consideration for all of my woodworking efforts.
And that was the job done, and here it is, in its home on the covered veranda of my house:
As you can see, the finish turned the feet, which I cut from a discontiguous slab, a darker color than the rest of the table, but it’s an effect I rather like. The clouded figure of the top shimmers beautifully in the morning light from the East, and the little imperfections quietly witness to handwork, something for me to fret over in my quietude at meals around the table. The horizontal beams at the top of each leg that mate with the battens, not visible in the photos, are identical to the feet, except of course inverted.
I do not think I am testing the permanent nature of this table by using it outdoors – though I may move it inside for a different practical reason: it is now the largest table we have, and has already made a couple of trips inside for big family gatherings. Rather, faced with a true forever wood that can endure against the elements, it seems only right that it should experience them and demonstrate its aplomb. I am glad in the end that I did not glue the centre joint of the top surface because it allows the two slabs to move and stretch a bit on humid days without cracking or busting the seam, and while this does mean they become un-flush for a day or two, they settle back in becoming flush once again when the weather dries out. The table can breathe.
I will inevitably make little corrections as the table and I get used to each other. I remain unsatisfied with the very rectangular shape of the stretcher, and when the time comes to break down and refinish the table I will add some curvature to the stretcher. I will also probably resurface the top perhaps once a decade, as it ages and my skill with a kanna (hopefully) improves. Part of the joy of using a wood that should outlive my bloodline to make a table of great permanence that can be disassembled and reassembled as needed is the anticipation of ongoing minor improvements, and the relationship I and future generations will have with it.
In the end, I still do not quite deserve this wood, because no one does. It is right and just that the Tasmanian government has banned the felling of any more of these trees, and it is right and just that the remaining wood is hard to come by and cherished. I am happy for the opportunity to make something permanent with this magnificently permanent and beautiful material.
Antone Martinho-Truswell is a professional zoologist and amateur woodworker. His work can be found on Instagram at @stjosephwoodworks, where he posts his projects, experiments, and failures, and takes the odd commission. If you enjoy his writing and want to learn more about his day job, his book, The Parrot in the Mirror, is available from booksellers online and worldwide.
To learn more about and to peruse our tools, please click the “Pricelist” link here or at the top of the page. To ask questions, please the “Contact Us” form located immediately below. You won’t be ignored.
Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, treacherous X, Harvard University, or H. Clinton’s IT dude and so won’t sell, share, or profitably “misplace” your information. If I lie may someone bukkiri my neck.
A 320mm (“shakuni”) bukkiri gagari handsaw with a kiri wood handle resting on your humble and obedient servant’s atedai workbench
Socialism is the philosophy of failure, the creed of ignorance, and the gospel of envy.
Winston Churchill
The goal of socialism is communism.
Vladimir Lenin
Thank you for visiting the C&S Tools Blog! This article will be a show and tell about a couple of unusual saws of a type not well know outside Japan. For that matter, they are no longer common inside Japan.
The Bukkiri Gagari Saw
The three saws pictured in this article are of a type of Japanese handsaw called a “bukkiri gagari.”
Terminology
Let’s begin with the second word in the name, “Gagari,” (gah/gah/rhi) which refers to a larger rip saw intended for rougher work. Usually forged heavier and stiffer than standard handsaws, these were once standard tools in every Japanese carpenter’s toolbox, used for ripping boards and cutting joints in timber frames. The teeth are made large to quickly eat lots of wood, but when properly sharpened, given the right set, and used correctly, they will make smooth cuts indeed.
Your humble servant has only seen the word gagari written using phonetic “hiragana” characters which are derived from Chinese characters but do not have any inherent or historic meaning, so while I can’t guess where the word came from, in exchange for a delicious chocolate chip cookie (with a glass of cold milk, please) I might be so bold as to suggest it came from the rough sound large rip saws make when ripping thinner boards.
Likewise, I’ve never seen the modifying first word, “bukkiri” (book/kee/reeh), written using other than hiragana, but even without a cookie bribe I can guess that “bukkiri” is a modification of the word “bukkiru,” which means to “chop off” something, for instance the head of a fish or an especially-corrupt politician. In this case, I believe it refers to the pointed tang having been chopped off short. So a bukkiri gagari is a larger rip saw with a shortened tang and an angled “shumoku” handle.
The Shumoku Handle
A shumoku mallet for striking small bells
The handle is especially unusual so let’s consider it next. The skewed handles in the photos in this article are called a “shumoku” (shoo/moh/kuh) 撞木 handle.
Shumoku is an interesting word. The Chinese character “Shu” 撞 means bell, while “Moku” 木means wood. In other words, a shumoku is a piece of wood for ringing bells. The image to the right is of a wooden mallet used to strike small tabletop bells during Buddhist ceremonies.
The shumoku in the video at this LINK is a tad larger, being motivated by a group of 17 jolly monks in a bell-ringing ceremony at Chion-in Temple (知恩院, Monastery of Gratitude, Jodoshu-sect) in Kyoto. Said to be the largest bronze bell in Japan, it seems to take a lot of work to make it sing!
I have no clue why this word is used for a saw handle, and those in the industry I’ve asked didn’t either. A mystery. Based on my long years of experience reading and writing in the Japanese language, it seems likely that the woodworkers that made and used this style of handle back in the mists of time gave it a name with a pronunciation similar to shumoku back in the days when few commoners could read or write, and centuries later when the came time to write the word using Chinese characters, someone decided to use the “bell wood” characters just to poke fun at the monks in their funny dresses (ツ).
Despite what those who like to portray the Japanese language as highly cultural and absolutely logical suggest, I can assure Gentle Reader it contains many instances of such strange “assignments,” just another reason why the written language is too often confusing.
Long, straight handles with oval cross-sections are more common in Japan, and certainly better known outside Japan. And the straight handle makes accurate cuts easier because one can readily sense if the blade wanders from a straight line in the cut. But, in some cases, the straight handle has three disadvantages. First, the handle’s length sometimes gets in the way when making long strokes in the tight spaces where carpenters are sometimes required to work, whereas a saw with a shumoku handle is shorter, and is easier to use from various angles, for example, when cutting a tenon or a housed dovetail from under a beam. Second, the straight handle depends on a high-friction grip by both hands to motivate powerfully, whereas the shumoku handle does not. And third, it’s more difficult to use as powerfully as the shumoku handle due to the angle of the user’s hands in-use.
Here’s are a Link to a video of a guitar luthier using a bukkiri gagari saw.
Two Examples of Bukkiri Gagari
The photo above shows two saws: the antique 320mm shakuni (1.2 shaku) bukkiri gagari as well as a longer 355mm “shakusan” (1.3 shaku) bukkiri gagari saw hand-forged and hand-sharpened for your humble servant by Nakaya Takijiro Masayuki, with teeth especially shaped for ripping hardwoods. A most excellent saw.
The shorter saw is over 150 years old, and according to the blacksmith’s hand engraving on the tang, was forged from “Tougo Reigo” steel, aka “Togo steel,” a British product made by the Andrews Steel Works and first imported into Japan by an officer who once served under Admiral Togo in the Japanese Imperial Navy and who borrowed the name of the famous military leader.
Admiral Togo was a small man who became a national hero for commanding the Imperial Japanese Navy’s forces when they kicked Imperial Russia’s butt. Job well done.
It’s a great saw, one your most humble and obedient servant has used frequently since purchasing it at a flea market in IIdabashi Tokyo many decades ago. I like the color it presents, the control it provides, and the compact size, but the teeth are little on the hard side as evidenced by a crack in one tooth. Togo reigo steel is well-known for being on the brittle side.
The shumoku handle attached to the Togo reigo steel saw is one your humble servant made from kiri wood with mulberry wood inserts and a black persimmon retaining wedge. These inserts are not standard, but an improvement I added to prevent the tang from wearing out the soft kiri wood. The wedge makes it easier to remove the handle for transport. It’s fancier than necessary, but I had fun making it. Another way to secure a shumoku handle is with a dovetail wedge inserted from the side, but I don’t like the weaker nature of this style, nor the feel of the wedge in the hand.
Gentle Reader will notice that the straight tang of the shorter saw has been cut off (“bukkiri”) square by the original owner long ago, and that the back of the blade curves away from the cutting edge. This curvature is standard for some rip saws.
The longer 355mm saw, by comparison, has a shumoku handle I made from tougher Japanese white oak with a more-or-less rectangular cross-section and is secured by friction alone.
The blade of the Takijiro saw is more-or-less straight, lacking the curve towards the end, and instead of the tang being straight it’s curved downwards in the direction of the teeth. This is not a standard blade converted into a gagari by chopping the tang short, but was planned to accept a shumoku handle from the time it was just a spark glowing in Takijiro’s forge, making it a dedicated, professional rip saw. Takijiro shaped this saw for me after one his master forged for a temple carpenter many decades ago, a craftsman I met at his workshop, and who gave me the opportunity to use, and fall in love with, his saw.
Please don’t tell my other saws I said this because they tend to be anthropomorphically jealous, and while saw cuts seldom make hearts bleed, they can make fingers fly.
Converting a Rip Saw to a Bukkiri Gagari
Gentle Reader can readily convert a standard Japanese rip saw into a bukkiri gagari by simply cutting the tang short and making a shumoku handle, as is the case of the shorter saw in this article, and making a simple handle to fit. The longer style saw is not available new, although Takijiro has forged a number of them over the years for our Most Beloved & Patient Customers.
While this article has been about dedicated rip saws, some craftsmen convert crosscut saws in the same way.
A safety warning is called for here, however, after all, they don’t call it the “nanny state” for nuttin. If you add a shumoku handle to a standard saw blade, be sure to at least cut off the pointy end of the tang. Otherwise, you’re likely to find your chest and/or arm leaking red sticky stuff compromising your color-coordinated woodworking togs, a simply devastating fashion faux pas. Herewith you’ve been duly warned.
Until we meet again, I have the honor to remain,
YMHOS
A bukkiri gagari rip saw This is one of a matched set of rip/crosscut saws custom-forged by Choujiro (Azuma-san) for a temple carpenter 30 or 40 years ago who never picked them up from the store where he placed the order. Notice the curved back peaking towards the end, the golden temper discoloration typical of handsaws made in Eastern Japan, and the old-fashioned forge-welded iron tang. With a toothline length of 330mm and progressive teeth (smaller towards the tang), this is a serious saw for serious work.
To learn more about and to peruse our tools, please click the “Pricelist” link here or at the top of the page. To ask questions, please the “Contact Us” form located immediately below. You won’t be ignored.
Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, treacherous X, Harvard University, or H. Clinton’s IT dude and so won’t sell, share, or profitably “misplace” your information. If I lie may the toothy gods of handsaws bukkiri my neck.
May it be a light to you in dark places, when all other lights go out.”
J.R.R. Tolkien, The Fellowship of the Ring
he title of this article references two things: A little knife, and a little wooden box, both uniquely and traditionally Japanese.
The Knife
The knife in question is called a “kiridashi kogatana” (kee/ree/dah/she koh/gah/tah/nah)) or just “kiridashi” for short. Your most humble and obedient servant has written about this Japanese woodworking and general utility knife at great length in this article: The Kiridashi Kogatana Knife.
Kiridashi are Japan’s traditional utility, carving and woodworking knife. Indeed, until about 30 years ago, every school child in Japan was required to have a little one in their school bag for sharpening pencils, cutting paper, carving wood, and many other classroom tasks. But it has always been a serious tool for serious work by adults, one owned and used daily by nearly every craftsman in the country for centuries, at least.
But what are the advantages of a plain, flat, thin knife like this? A good question, one that most Westerners who haven’t trained in Japan naturally ask, and one that deserves a good answer. So let’s list some.
Sharpness: Just as our chisels and planes, the blades of our high-quality, professional-grade kiridashi are of hand-forged laminated construction with a hollow-ground ura which makes them the easiest and quickest little cutters in the world to make frightfully sharp. And don’t forget, the love of sharp things is deep in the Japanese blood. You may find the articles at the following links amusing: In The Blood, Kireaji
Carry and Storage: Kiridashi are easy to store and carry because they are flat and thin. Hardware stores sell cheaper versions of these little cutters with wooden scabbards, but this makes them bulkier. Our kiribako boxes are perfect for safe storage.
Precision: It’s easier to make fine, precise cuts with a kiridashi than a thick, double-beveled Western-style knife with wooden scales because the flat, thin blade provides a better view of the work, provides better sensory feedback, and with fingertips located safely closer to the cutting edge, improved control.
Cost effective: The kiridashi is the very essence of a cutting tool with no frills, no handle, and no expensive surround stereo system, just a simple, easily sharpened and fiercely-sharp blade.
Of course, kiridashi can be purchased with wooden handles and full wooden scabbards, or the user can make one to his taste easily enough. Your humble servant has made scabbards for those kiridashi he brings to jobsites for the extra protection they afford during transit, but they aren’t otherwise necessary and offer no advantage in the workshop, where I use a bit of cardboard as protective sheath instead.
So that explains the “Knife,” part of this article’s title, but what about the “Presentation Box” part? That’s next.
The Box
Being so popular in Japan, there is an extremely long history here of gifting better-quality kiridashi kogatana knifes to friends, families and fellow workers who use them. In fact, those procuring a kiridashi as a present have historically purchased them with a special presentation box of a type called a “kiribako” made of a wood much loved in Japan called “kiri ” (paulownia tomentosa). These little boxes typically have handwritten calligraphy on the lid describing the contents.
Regarding kiribako, It’s not an overstatement to say that one cannot fully understand the Japanese people until one understands kiri wood and kiribako.
Kiri trees have large leaves and beautiful flowers, grow extremely quickly, and produce a lightweight fragrant wood Japanese ladies love for cabinetry and chests used for storing clothing. Indeed, it was once common for fathers to plant a kiri tree at the birth of a daughter, and have the wood of the same tree made into a dowry chest or cabinet for her marriage when the time was right.
Due to popular requests going back years, we now carry kiribako boxes with hand-written calligraphy designed to fit our hand-forged kiridashi kogatana knives. They make excellent gifts and presentation pieces. And they’re not at all expensive.
Our boxes are solid-wood traditional construction, made in Japan by a Japanese specialist box-maker located in Niigata Prefecture, with a tight-fitting slip-on lid. They also come with the characters “Kiridashi” written by hand in ink on the lid along with the blacksmith’s name (Mr. Masuda) and his personal chop. Inside the box is a stamp that says “Shirogami” referring to the type of steel Mr. Masuda uses to make our kiridashi.
Given some time, and at no additional cost, Beloved Customers can request personalized calligraphy, such as the recipient’s and/or presenter’s name, the occasion, and even a date, in the Japanese language of course.
If you’re looking for an unusual, extremely traditional and classy gift for someone that likes beautiful, useful, sharp tools, this might be just the ticket. You won’t find them anywhere but C&S Tools. If you’re interested, please see the pricelist at the link below. To contact us please use the form below.
If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page to find our products and use the “Contact Us” form located immediately below.
Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google or fascist facebook and so won’t sell, share, or profitably “misplace” your information. May all my kiridashi chip and break if I lie.
Perfection is a necessary goal, precisely because it is unattainable. If you don’t aim for perfection you cannot make anything great, and yet perfection is impossible.
Leonard (the cutter, not tailor) – The Outfit (2022)
We occasionally hear of people (not Beloved Customers, of course) complaining about Japanese chisels. Like much idle opinion expressed on the internet, this squirts and bubbles forth from a few vocal amateurs lacking real experience or skills, but it’s undeniable that, compared to the sharpened screwdrivers sold as chisels in Western countries nowadays, a little special knowledge, extra diligence and some actual hand skills are necessary to meet the challenges of professional-grade Japanese chisels.
In this article your humble servant will list some challenges one may face when first learning how to use and maintain Japanese chisels, and will suggest straightforward solutions for he who has ears to hear. But, because nothing except a movie studio executive’s reserves of morality exist in a vacuum, allow me to first provide some background about the way our hand-forged chisels are made, as well as the division of labor between the craftsmen involved, and explain how this influences modern attitudes among professional craftsmen.
Terminology & Relevant Links
The terminology used in this article may be unfamiliar to some, so to avoid confusion, allow me to immediately clarify four of them. In addition, the articles at the links below contain relevant information you may find useful.
“Ura” refers to the entire side of a Japanese chisel’s blade opposite the surface with the brand, not including the neck, of course.
“Uratsuki” is the hollow-ground depression at this same surface. This surface is tastefully black in our chisels. Others prefer this area to be polished.
“Lands” refers to the planar, polished surfaces at the ura surrounding the hollow-ground uratsuki on four sides.
“Itoura” is the most important of the four polished lands (itoura, side lands, and neck land) surrounding the uratsuki, being located immediately adjacent the cutting edge and forming one half of it. It’s important because, without it, the blade won’t cut.
The articles at the following links may prove informative, or at least amusing.
Beloved Customer has probably visited neither a modern tool factory nor a traditional chisel smithy, so a brief summary of the steps our blacksmiths employ in producing a hand-forged, high-quality, professional-grade chisels may provide useful insight.
Please note that the hardware store-grade Japanese chisels mass-produced for export that Westerners are accustomed to are not produced this way, and their performance suffers accordingly.
The Smithy
Our chisels are handmade by either single blacksmiths, or master & apprentice blacksmith shops, or father & son smithies using mostly old equipment, except for Mr. Usui of Sukemaru brand pictured below who works alone nowadays, has an engineering degree, and loves precision equipment.
Mr. Usui Forging an atsunomi chisel
Nakaya Takijiro (sawsmith) at his forge
Nakaya Takijiro’s forge, originally made for forging swords
Mr. Nakajima’s workshopMr. Nakajima, chisel blacksmith (ret.) in his workshop
Materials
The process begins with materials.
Nowadays, the blacksmith purchases processed iron and steel from wholesalers in ready-to-use strips. In the case of C&S Tools’ chisels, our blacksmiths use Hitachi Metal’s Shirogami No.1 steel exclusively along with a variety of low-carbon steel/iron called “gokunantetsu” 極軟鉄 meaning “extremely soft iron.” Neither of these products are currently being produced.
With materials in hand, the blacksmith will use his forge fired by gas and charcoal and fed forced air by an electric blower to help create the necessary atmosphere and high temperatures.
Just in case you are interested, the traditional Japanese hand-operated blacksmith’s bellows is a rectangular wooden box with a horizontal wooden rod penetrating one end attached to a flat wooden piston inside the box sealed with leather or cloth gaskets as shown in the photos below. Sometimes the box is lined with glass for smoother operation and a better air seal. The blacksmith, usually sitting on a cushion on the floor of his smithy, or on a stool in a pit near the forge, operates this contraption with his left hand or left foot (yes foot) while manipulating hot metal with hammers and tongs with his other hand(s). Several of our blacksmiths still have these old bellows gathering dust in their workshops, but none use them anymore.
Forging & Laminating
Quality Japanese woodworking chisels are hand-forged and of laminated construction.
On the other hand, low to medium-quality hardware store-grade chisels, which have replaced all but a very few of the quality chisels made in Japan nowadays, and comprise all the chisels produced for the export market, are not hand-forged by trained and experienced master blacksmith but are mass-produced by factory workers in cookie-cutter fashion with dies and presses using a lower-grade pre-laminated steel (aka “rikizai” or “fukugozai”) produced by steel mills, a commercial product originally developed for stamping out supermarket-grade kitchen knifes by the thousands. The steel used is Blue Label steel at best, but ordinarily a cheaper equivalent material such as common SK is used. This mass-production technique typically involves only a single “heat,” and is over in just two, at most three, stamps of large presses. BTW, you may want to consider this fact next time you pay hundreds of dollars for a mass-produced Japanese kitchen knife.
The resulting products look good in their colorfully printed plastic and cardboard containers, are inexpensive to make, and quite profitable, but the crystalline structure of their steel, an essential physical detail invisible to the naked eye, and one that determines a tool’s cutting and sharpening performance, is greatly inferior to the results the more traditional, labor-intensive techniques and highest-quality materials our blacksmiths employ routinely yield.
In the traditional method, the blacksmith heats, cuts, and shapes strips of iron and steel into the necessary components using the heat of his forge, an anvil, various tongs, chisels and shears.
He then forge-welds a slip of high-carbon steel to the low/ no carbon iron strip which will become the body of the chisel using his forge, an electric motor- powered spring hammer (or hydraulic hammer in one case), his anvil, tongs and hand hammers as shown in the photos below. No presses.
Heating the iron strip (gokunanatestu) which will form the body of a chiselPlacing the high-carbon piece of steel on the iron strip for forge-laminating
With the lamination work done, he then uses these same tools combined with a few open-faced hand-dies to shape the chisel.
This process of forge-welding and shaping involves at least three “heats” (heating and cooling cycles) combined with hundreds of hammer blows. The purpose of all this dramatic fire, violence and unholy racket is to not only (i) shape the chisel blade, but to also (ii) reduce the size of the carbide crystals in the steel and (iii) distribute them evenly, preparing the “fine-grained” crystalline structure of the steel so important to quality cutting tools and indeed modern civilization.
Modern mass-produced and low-quality chisels do not go through this process to the same degree and their crystalline structure suffers greatly in comparison, a difference visually indiscernible without destructive testing or the aid of a scanning electron microscope, but one that craftsmen and warriors have highly valued since steel replaced stone, copper and iron in their tools, a difference once considered supernatural.
Annealing/Normalizing the Blade
The blacksmith will then anneal the blade by heating the steel to a specific “recrystallization” temperature”(about 750˚C or 1380˚F for Shirogami No. 2), and allowing it to “soak” at that temperature for a specific amount of time. He will then place the blade overnight in a loosely-sealed container filled with rice-straw ashes, a high-carbon/low oxygen atmosphere which will “relax” the steel removing internal stresses and making it dead soft and more uniform, chemically speaking. While not sexy, this step is critical to making a high-quality blade, and while it has been used for by the best swordsmiths for thousands of years, it’s absolutely scientific.
The blacksmith will then refine the shape of the blade using hammers and electric grinders.
Quenching the Blade
Quenching is the magic at the heart of The Mystery of Steel. This process begins with the blacksmith applying his own special “medicine” to the blade, an unappetizing, gloppy brew made from various secret materials, usually including sharpening stone mud, clay, rice straw ashes, steel filings, dragon dandruff & etc., that serves to control differential cooling.
When this medicine is thoroughly dry and everything is just right, he will heat the blade in a gas/charcoal fire to 800˚C (1470˚F) for a very specific time period , after which he will plunge it into water “quenching” and quickly cooling it. He may repeat this step one or two more times.
This sudden cooling creates drastic changes in the organization of the iron and carbon molecules in the steel portion of the blade. On the other hand, the iron “jigane” body of the blade lacks the essential carbon ingredient and so its hardness does not change significantly.
Extremely hard particles called “carbides” are instantaneously created during this process. These become locked into a particular crystalline structure in the steel with a greater volume than before quenching. That’s right, the steel swells as it’s suddenly cooled.
As you would expect, this produces high differential stresses in the blade causing the steel to warp, movement the blacksmith must compensate for when shaping the blade before quenching, and while less sexy and more vexing, sometimes by corrective measures after quenching.
Naturally, the chemical nature of the steel selected combined with the blacksmith’s mastery of his craft, and of course the whims of the Gods of Handsaws, greatly influence the resulting warpage, demanding great skill and some luck if disastrous failures and expensive wastage are to be minimized.
A Japanese swordsmith quenching a long sword in the photo above. Before quenching the blade is straight, but it will warp during this step. This warpage often becomes an intentional design feature in many swords including the one shown in this photo. Please note that the “grain” pattern visible between the white hamon and “hi” groove is not a defect in the steel, but a highly-prized design feature in this art form.
Tempering the Blade
After quenching, the high-carbon steel portion of the blade is excessively hard and brittle, too brittle for practical use in fact, so the blacksmith will next “temper” the blade by reheating it to 300 °C (570˚F) ~ 400˚C (750˚F), a temperature lower than that used for forging, for a very specific time period. His precise control of time and temperature in this process will make the difference between a fine blade and a lump of costly scrap.
Tempering reduces the amount of hard carbides in the steel, producing a less-rigid crystalline matrix, reducing hardness, and most importantly, increasing toughness.
Every blacksmith has his own techniques, but his selection of steel and his skill in using it are critical. Some steels are easier to forge and heat treat than others producing fewer failures and rejects greatly impacting productivity.
At this point in the process either the blacksmith, his apprentice, or a subcontractor will grind and sand the blade to final shape and finish. He will also grind and finish the hollow “uratsuki” to form the “ura.”
Finishing the Blade
The next few steps are where things can go crazy if the blacksmith decides to refine the shape and finish of the tool by investing extra time, effort and tools such as fine-grit grinders and sanders, and hand files, for it takes a careful eye, an artistic sense of line and proportion, a steady hand, and many hours to achieve the perfect surfaces found in the best chisels as represented by the products of the Yamazaki brothers under the “Ichihiro” (or “Hidari no Ichihiro,” or “Tsuki Ichihiro”) brand.
The chisel in the photo at the top of this page shows the blade of a beautifully shaped and finished large fishtail shinogi ootsukinomi by Nora.
Indeed, this extra cosmetic work, which does not influence performance in any way, will increase the cost of producing a single chisel of the same performance 5~10 times. Would Beloved Customer be willing to expend that much additional money for improved cosmetic appearance in a working tool? Your humble servant has scratched that sculptural itch many times (too many times, says She Who Must Be Obeyed), but most craftsmen are not willing to lay out the additional hard cashy money.
Mr. Yamazaki
In fact, many Japanese craftsmen, even those who have a fetish for beautiful tools and are willing to pay the necessary funds to procure them, will usually leave such tools safely at home or in the workshop to save them from Darwinian adventures, and take a less valuable set of chisels to the jobsite instead, another layer of expense. Ah, the sacrifices we make for art! (ツ)
A 42mm Oiirenomi by Hidari no Ichihiro, the Yamazaki Brothers (RIP). Far from new, but beautifully shaped and finished, none better in all Japan.A kotenomi in the Chiyozuru Korehide style by Kiyotada. A serious cutter that has seen lots of use, it’s beautifully shaped, but the filework is not quite as nice as the Yamazaki brother’s work, IMHO.
The Sharpener
At this point, the blacksmith’s job is done and the blade is handed off to a sharpener. Please note that some blacksmiths, including Mr. Nakano, our master plane blade blacksmith, prefer to sharpen their blades themselves, and for good reason.
Sharpeners typically do piecework and so strive to do as many chisels as they can as quickly as they can. The problem we face lately is that the number of skilled sharpeners in Japan has drastically decreased leaving us few choices. Sometimes the quality of the sharpening job is less than perfect, something that is also reflected in the low cost and less-than-perfect precision of the ura lands. We think it’s a fair trade. Please note that these are all conscious decisions agreed to in face-to-face discussions with the craftsmen, not default specifications.
Mr. Takagi (adze smith & sharpener RIP) at his sharpening stones
The Handle Maker
Mr. Hasegawa, handlemaker, in his workshop
The sharpened chisel blade next goes to a handle maker. He has an important job because the handle is the interface between Beloved Customer and the tool, and through which tons and tons of impact forces are transferred to the cutting edge.
Mass-produced chisel handles often have poor tolerances that don’t accommodate the steel hoop and ferrule well, or that don’t transfer the hammer’s energy properly producing tiring harmonic vibrations in the tool. We don’t use inexpensive, mass-produced handles but have Mr. Hasegawa custom make them himself from select wood to match our blades and the selected metal furniture. Even then, it is wise for each end-user to perform a final setup themselves for a more perfect fit.
To conclude the discussion about production methods, it is important to understand that our tools are produced more in keeping with traditional methodologies and division of labor by specialist craftsmen, rather than automated mass-production methods using unskilled factory workers, cheap materials, and higgledy-piggledy techniques.
The Chisel Owner’s Role
Why is all the stuff discussed above relevant, you ask? Good question. It matters because until recently in Japan, and in even Europe, it was standard practice for a craftsman to commission a chisel blade directly from a blacksmith who would provide a shaped, ground and filed but unsharpened piece of metal with a squared-off end cut at more-or-less 90˚.
It was the end-user’s responsibility to grind and sharpen the blade’s blunt cutting edge himself. Ergo no sharpener.
He would purchase the iron furniture (hoop or katsura and kuchigane or ferrule) from another specialist blacksmith shop, and make his own handle with his own tools from his own wood. Ergo no handle maker.
It’s only been recently with the rise of large cities and cheap distribution networks made possible by rail and roads that finished products have become commonly available as retail products.
Please remember that, despite what the movies present, for many thousands of years prior to the Meiji period and the Westernization of Japan, it was a not a single, united country, but a collection of desperately poor medieval fiefs ruled by ruthless despots in which hundreds of thousands of common people, including woodworkers, died every year due to internal wars, illness and famine. Craftsmen too were poor and had little disposable funds.
My point is that self-respecting craftsmen worldwide disdained paying others to either sharpen their blades or make any components for their tools that they could make themself. The remnant of this historical fact seen nowadays is that the experienced craftsman in Japan does not expect a perfect tool, but expects to perfect his tools himself to his own taste.
Let us next get to the heart of the subject and consider the typical challenges one must deal with in the case of hand-forged chisels, beginning with the most common one.
Challenge No. 1: The Ura Is Not Planar
Ideally, the polished lands surrounding the four sides of the hollow-ground uratsuki are all perfectly planar, but as the erstwhile cutter quoted at the top of this article said, “Perfection is Impossible.” And your humble servant would add that it ain’t even necessary.
Despite this obvious truth, some inexperienced Gentle Readers expect the lands of the ura surrounding the hollow-ground “uratsuki,” the area corresponding to what is called the “flat” in the case of Western chisels, to be perfectly planar, even though Western chisels seldom have perfectly planar “flats,” but only what look like flat surfaces. Your humble servant agrees that perfection is nice, but it is not a reasonable expectation in the case of medium-priced professional-grade tools.
Gentle Readers who expect the appearance of CNC precision in their tools should either stick with the sharpened screwdrivers China produces in such abundance and which are sold in the West as “chisels,” or plan on spending 5~10 times the cost of mass-produced chisels, assuming you are able to find anyone that makes such quality nowadays.
In any case, an ura that is not perfectly planar is not a defect. The article at this link can help you understand how to deal with ura problems in an efficient and professional manner.
Challenge No. 2 – The Blade Chips
Our blades are intentionally made harder than most Japanese chisels produced nowadays because hardness is essential in a professional-grade chisel. As explained at great length in the article linked to above about “Professional-grade Chisels,” on condition the crystalline structure of the steel is what it should be, a hard blade will usually become sharper, will cut more wood, and will stay sharper longer than a relatively softer blade thereby reducing the frequency of sharpening, consequently increasing the professional’s productivity. This is an essential performance criteria in a professional-grade chisel.
But hardness is not all blue bunnies and fairy farts because a harder blade is less tough than a softer blade and can be damaged if abused. Warranty claims from amateurs and fools who use their chisels as if they are screwdrivers or scrapers instead of finely-made cutting instruments and then blame the blacksmith for the damage their ham-handed abuse wreaks are exactly why nearly all Japanese chisels produced nowadays are intentionally made softer and less efficient. Most are still harder than Western chisels, make no mistake, but they are too soft for professional use.
Our chisels, on the other hand, are forged and heat-treated to maximum practical hardness as required by top-tier professional Japanese woodworkers.
Beloved Customer should adopt the four solutions described below so as to not abuse your chisels thereby preventing chipping and keeping your eager blades cutting as long as possible.
Solution 1 – Maintain a Proper Bevel Angle: Please pay careful attention to maintaining a proper bevel angle, one that will adequately support the extreme cutting edge against chipping. 27.5~30˚ is standard. Why is this important? Improper bevel angles are the primary cause of cutting-edge chipping. The solution? Procure a bevel angle gauge, use it frequently and correctly, and pay attention because the construction of Japanese chisels is conducive to the bevel angle gradually decreasing over many sharpening sessions. Please read about Supernatural Bevel Angles for more details. Silver crosses and garlic necklaces are optional.
Solution 2 – Cease and Desist Tool Abuse: Your chisel is a highly-refined tool specialized for cutting wood and must not be to be used for anything else. Period. Don’t use the cutting edge of your chisel to open paint cans, turn screws, scrape gaskets, or even pry wood chips out of mortise holes because such abuse will place forces on the cutting edge in directions it is not designed to handle dulling the blade quickly, and maybe even causing it to chip. Seriously.
Solution 3: Shun The Chisel Wiggle: Don’t make your tools perform the lewd “chisel wiggle” when cutting mortises, for such unseemly gyrations will damage their cutting edge. Just don’t do it. For a more detailed explanation, please see the article at this link.
Solution 4: Cut Only Clean Wood: Don’t use your precious chisels, planes or saws to cut nails, screws, concrete, rocks, sand or dirt. What? None of the wood you use is infested with such evil substances? How do you know unless you check? Please see the article linked to here to better understand The Mystery of the Scratched Blade.
Challenge 3 – Blades are Difficult to Sharpen
As mentioned above, the blades of our chisels are especially hard by design to become sharper and stay sharper longer than standard chisels thereby improving the craftsman’s productivity. But given the same area of steel, measured in square inches or square millimeters, harder steel takes more time and/or abrasive effort to sharpen, as I’m sure you’ll agree. So how can one sharpen this harder steel efficiently?
Solution 1 – Use Diamonds: Use quality, flat diamond stones/plates instead of regular stones (although regular stones are almost as quick if used properly and a lot cheaper).
Solution 2 – Use Skill: Learn how to sharpen your chisels in a professional manner. We have a series of 30 articles beginning at this LINK about sharpening Japanese blades that may prove helpful.
Solution 3 – Reduce the Frequency of Sharpening: There seems to be two or three mindsets about sharpening in the world. One is what I call the Teutonic Solution, which is to make the chisel’s blade soft and easy to sharpen. This also makes the chisel tougher and less likely to chip, while at the same time obviating the need for quality steel, advanced blacksmithing techniques, or the exercise of rigorous quality control, protecting the manufacturer and retailer against warranty claims. On the other hand it means the blade will never cut very well, and it will dull quickly. For those who don’t need sharp blades and/or lack sharpening skills, this is a good solution, I suppose, but the poor-quality work such blades can accomplish, the excessive time and sharpening stone they waste, and their decreased useful lifespan is unacceptable to professional Japanese woodworkers.
The other mindset I call the British Solution, which means a medium-hard blade; A compromise yielding more efficient, but nonetheless compromised results.
The third mindset is the Japanese one, which is to make the blade as hard as practical. It was once the same mindset in Europe and America too, but no longer. Please see the article at this link for details.
This solution is to use your blades in accordance with the principles detailed in Challenge 2 above, and maintain them properly thereby reducing the frequency of sharpening.
Solution 4 – Reduce the Amount of Sharpening: The essence of this solution is to sharpen your blades efficiently, so that less metal must be abraded/polished and turned to mud during each sharpening session. For this solution to be effective Beloved Customer must develop an essential skill, namely a sense of when your tool has dulled to the point where it is best to stop work and resharpen the blade while it can still be quickly and efficiently resharpened thereby saving time, steel and stone, instead of banging away with the chisel until the edge deteriorates to the degree it will take major effort and excessive time on rough stones to resharpen. This is a vague skill that takes time to obtain and self-control to implement, but nonetheless it’s an important professional skill and one worth developing.
Challenge 4 – Handle Setup is a Pain in the Assets
Your humble servant has performed setup procedures on hundreds of chisels, and while it can be pleasantly meditative at times, indeed the perfect opportunity to bond with a new tool, I acknowledge it’s sometimes a burden. We recommend Beloved Customers perform a full “setup” on the chisels they purchase from us in accordance with the instructions in the article at this link. Why? Because it will help the chisel’s handle last longer and sometimes will make the chisel perform better. That said, while not doing all the setup steps described in the article will not make your chisel self-destruct, it may cause you to inadvertently damage its handle over years of hard use.
Compromise Solution – Setup Only The Hoop: If you can only do one step in the setup procedures for your chisels, chamfering and fitting the hoop is the most important. All else can wait if it must.
Setting up the katsura hoop is the single critical task in chisel setup. Failure to do so can lead to the damage seen in these photos over years of service, especially if a hammer with a domed face is employed.
Challenge 5 – The Mystery of the Disappearing Itoura
As mentioned above, the itoura is the land at the ura located immediately adjacent the cutting edge. In fact, it forms one-half of the cutting edge. Sharpening the blade’s cutting edge makes the blade gradually shorter and the itoura gradually narrower, eventually making it disappear entirely, unless proper technique is employed. Please note, however, that a narrow itoura is not a bad thing up to the instant it ceases to exist. So, how best to deal with the Mystery of the Disappearing Itoura?
Solution 1 – Balance the Abrasion of the Itoura and Other 3 Lands of the Ura: Besides making the blade sharper, abrading the ura uniformly during sharpening produces the following two consequences: (1) All four of the lands surrounding the uratsuki (hollow-ground depression at the ura), especially the itoura and side lands (ashi), gradually become wider, each to varying degrees; and (2) The uratsuki gradually becomes shallower. The solution your humble servant presents here is to pay attention to the itoura’s width, and to abrade the ura at a pace and in a focused manner that maintains a useful itoura even as the blade becomes shorter, but without excessively wearing out the uratsuki. A balancing act of sorts.
To do this, besides having an attentive eyeball, and while it may seem counterintuitive, you must not focus abrasion evenly over all four lands of the ura, but instead focus finger pressure and therefore abrasion primarily at the itoura instead, while at the same time keeping the 4 lands at the ura more-or-less planar. This is counterintuitive to people accustomed to the uninterrupted slab of apparently (but seldom actually) flat steel on Western chisels, but it requires the sharpener to apply focused, fingertip, point control instead of just chugging a beer, plopping the blade’s ura on the stones, leaning in and grinding away like a badger digging a juicy gopher out of its hole. This hand/eye skill is one the woodworking gurus selling books and classes either don’t know or overlook, shame on them, and the goobers on NoobTube never even consider.
Solution 2 – Restore the Itoura Through Uradashi and Uraoshi: The Mystery of the Disappearing Itoura is typically more of a problem for plane blades than chisels, but the same techniques used for plane blades can be used to restore the itoura of a chisel through a couple of processes called “Uradashi” and “Uraoshi” described in great detail at the article linked to here. However, please note that, while these techniques work well on plane blades and carving chisels, they do not work as well (or at all) on narrow chisels due to the extra-rigid construction of their blades. Consider yourself duly warned.
Solution 3 – Sharpen the Ura Using Ultra-fine Stones Only: Here in Japan the sight of chisel and plane blades owned by professional woodworkers, especially carpenters, with the ura worn away entirely is common. These craftsmen work in the field under great pressure, with limited access to tools, and often lacking adequate time to sharpen their tools gently. Consequently, to save time, instead of switching to a fine-grit stone, they will sharpen both the bevel and ura of their blades using only a single rough or medium grit stone. The problem is that, once the ura is in good shape, it seldom needs to be worked on anything but fine finishing stones, so working it on rough or medium stones during each sharpening session wears away the ura’s lands quickly and consequently prematurely wears away the ura. If you value your tools, and expect them to serve you a long time, I encourage you to use only fine-grit stones on the ura of your blades for routine sharpening, and save the rougher stones for occasionally remediating chips and other defects. Your tools will thank you.
The beautiful ura of a new Hidari no Ichihiro chisel. Please note that should the itoura on this chisel evaporate some day, uradashi cannot be used to restore it because the “U-shaped” steel lamination in the blade is just too narrow and too darn stiff.
Challenge 6 – The Uratsuki Dissapears
As mentioned in Challenge 5 above, sharpening the ura’s 4 lands abrades them making them wider, and at the same time, the hollow-ground uratsuki they surround, shallower. Appearance aside, a shallow uratsuki is no big deal except that the resulting wider lands take more time and stone to polish with each sharpening session, a problem because time is money and good stones ain’t free.
Solution 1 – Employ Balanced Sharpening: This solution is similar to Solution 1 in Challenge 5 above, but somewhat the inverse. As described in our series of articles about sharpening Japanese tools, unless there has been major damage done to the cutting edge, such as a chip or busted corner, it is seldom necessary to use anything but your finest grit sharpening stone to polish the ura. What typically causes the uratsuki to mysteriously disappear, however, is a craftsman using only a single grit of stone, usually a rougher one like 800 or 1000 grit, to frequently sharpen both bevel and ura in the interest of saving time. Don’t get me wrong: this is an absolutely valid sharpening strategy, one frequently employed by professionals under pressure, but it’s hard on chisels and wasteful long-term. Even if you are in a hurry, the time spent working the ura on a finer 6,000 grit stone instead of quicker-acting rough stones is a good investment in your chisel, IMHO. But on the other hand, time is money….
Solution 2 – Accept the Dictates of Fate: No one is getting younger except me and thee, but chisels have a useful lifespan, usually defined as the quantity of sharpening sessions it endures rather than simple time. When, after many sharpenings, the uratsuki of Beloved Customer’s chisel bottoms-out despite your best efforts to preserve it, I recommend you smile at it warmly when you are alone together, call it a good and faithful servant, and keep using it until nothing is left but the handle and the neck, for even then, it will be a better friend than any chisel-shaped Chinese screwdriver, even if the label says “Made in Germany.”
YMHOS
The diminished ura of a still-useful oiirenomi chisel. A good and faithful servant indeed.
A few relevant articles can be found at the following links:
If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page to find our products and use the “Contact Us” form located immediately below.
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