Handsaws: Some Guidelines to Aid Precision

A famous wood block print by Katsushika Hokusai titled ” Mount Fuji Seen from the Mountains of Totomi,” one scene in thirty-six. With pre-big-bang Mount Fuji in the background, a group of four sawyers, and judging from the mother and baby in the foreground, probably including at least one family, are sawing boards from a huge timber on the very mountain where the tree was felled. Two men are sawing away with maeibiki ooga saws, one from above and another from below, while a third sharpens a saw underneath. OSHA approval was not obtained for this working arrangement, oh my! They probably slept in the rough shelter erected at the left. A brutal, if scenic, lifestyle with abundant, fragrant fresh air.

“I see” said the blind man as he picked up his hammer and saw.

Anon

Cutting joints connecting one piece of wood to another, such as mortise and tenon joints, bridle joints, dovetails, etc. using only handtools is not difficult, but most people find, at least initially, that executing them to fit together tightly without slop or unsightly gaps can be challenging.

The ability to routinely and quickly cut tight, workman-like joints with a handsaw is a critical skill for the professional that specializes in making limited runs of custom furniture and casework because the appearance of exposed joints is a direct, long-term reflection on his standards of quality. And while it may not be a critical skill for the amateur who produces high-quality woodwork, it is nonetheless extremely satisfying, especially if the cabinets, furniture or casework he makes will remain in his house or with family where any poorly-fitting joints will silently laugh at him with “open mouths,” as the Japanese saying goes, over many years. I hate that!

So, how does one go about improving one’s skill with handsaws thereby avoiding the mocking glances and silent, but nonetheless snide, remarks of sloppy joints? In this article your most humble and obedient servant will be so bold as to provide some guidelines I have shared with friends and Beloved Customers over the years, but which I have never before compiled into a single document. Please let me know in the comments below if these techniques prove useful.

The Saw

Of course, hand-cut joinery is accomplished using handsaws, tools that vary widely in quality and performance, so it is appropriate to begin this discussion with an explanation of the features a high-performance handsaw should incorporate.

In your humble servant’s well-informed opinion, the handsaw is by far the most difficult woodworking tool for the blacksmith to produce. Sadly, there are few skilled blacksmiths producing handmade saws nowadays, and while new companies producing pimped-out high-priced backsaws targeting amateurs have sprouted up, many of those exhibit performance inconsistent with the high prices their manufacturers demand. Imagine that….

But never fear, for below is a list of key things Gentle Reader should look for in a high-performance, professional-grade handsaw to be used for precision joinery.

The Plate

Whether Western or Japanese, the “plate” of a saw (the piece of sheet steel that comprises the blade) is its most important component. It must be adequately hard to resist bending and buckling, and so the teeth cut into it can be made sharp and stay sharp a long time, but not so hard the blade will crack or the teeth break off. This is a delicate balance. Sadly, most manufacturers err on the side of softer and duller. Sigh…

The best handsaws are made from plain high-carbon steel with a fine crystalline grain structure. Thus it has always been, and for good reason. Sadly, high-quality steel of this sort is difficult to procure nowadays.

Most of the new American and European manufacturers of backsaws, as well as all the Japanese manufacturers of replaceable-blade handsaws, make their saw plates from pre-hardened, thickness-sanded steel purchased in sheets or rolls, metal never touched by a blacksmith. This is a cost-efficient material that eliminates the need for blacksmithing skills, but it has a few serious limitations that negatively impact a saw’s performance.

In the case of Japanese blades with the discolored, hardened teeth, after the plate has been stamped out with dies and a press, or cut to shape with a laser, the teeth are shaped by diamond grinders, set is applied by machine, and the blade is passed quickly through an induction coil formed by two metal blocks charged with high voltage electricity, suddenly heating the teeth in a technique called “shock hardening.” The plate never slows down, and as the red-hot teeth exit the induction coil, they pass through a coolant spray which instantly quenches them creating a hard, crystalline structure in the metal.

Most Western backsaws are made using similar materials and processes but without the induction hardening step.

210mm Dozuki saw hand-forged by Nakaya Takijiro, the ultimate handsaw for precision woodworking.

Taper Grinding

A high-performance saw’s plate will be taper-ground in at least one direction, with the plate made thinner at the back than at the teeth, providing extra clearance in the cut, increasing as the blade cuts deeper into the wood, reducing friction between wood and plate for a smoother cut with less effort, and reducing the risk of buckling.

Handmade Japanese handsaw blades are of course double-taper-ground, as once were all quality Western handsaws too, but sadly neither replaceable-blade Japanese handsaws nor modern Western backsaws are taper-ground to any degree. John Disston would puke.

Unfortunately, too many modern users of handsaws, lost in a Twitter world, have become entirely inured to terminal Chinese Logic, such that most are incapable of even considering qualities they can’t instantly infer (correctly or not) from a photograph on the internet. These confused souls deserve our pity.

Gentle Reader would be wise to place his priorities regarding performance above outward appearance, for neither a prettily-finished exotic hardwood handle, a beautifully sanded/polished finish on a sawplate, nor an eye-catching etched brand contribute diddly to a handsaw’s performance or the precision of the cuts it can make.

Hammer Tensioning

Hammer tensioning is an ancient technique whereby the sawsmith or saw sharpener rests the plate on an anvil and taps the plate with his hammer creating small dents in specific areas. Each tiny dent deforms the metal making the plate slightly thinner at the point of impact while at the same time displacing a corresponding amount of metal away from the point of impact. Being constrained from expanding as much as it wants to by surrounding metal, the accumulated strain of many dents creates internal stresses that want to make the saw wider and longer. Taken too far, these stresses will make the sawplate buckle or oilcan, but if done just right, for all practical purposes the sawplate will remain flat and stable.

Why bother with all this hammering? Clearly Gentle Reader is exceptionally perceptive to pose this question, and accordingly your humble servant quivers with joy at the prospect of clarifying an elegant and ancient mystery, one that is still employed to good effect in high-quality modern circular saw blades as I learned during recent meetings in Nagoya with three of Japan’s largest circular saw blade manufacturers.

So here’s the reason: As a sawblade heats up due to friction in the cut, the metal of course expands, but not uniformly over the blade’s entire surface. This differential heating and differential expansion causes a sawplate that has not been hammer tensioned to temporarily warp, increasing friction in the cut even further, and making the cut wander thereby ruining the precision of the cut, and in the worst case, causing the saw to buckle. The residual stresses produced in a saw’s plate through proper hammer tensioning will counteract and cancel out stresses produced in the sawblade through friction heat preventing the plate from buckling, excessively warping, or oil-canning, with the result that the saw will cut straighter and cleaner with less effort even as it heats up.

I don’t know who invented this technique far back in the mists of time, or where, but it is genius-level craftsmanship.

The better-quality Japanese replaceable-blade handsaw makers have taken a page from the circular sawblade manufactures and run their sawblades through a pair of opposed steel rollers which induce stresses in the steel similar to hammer-tensioning by hand. I may be wrong, but I am unaware of any modern Western backsaw makers that either hammer-tension or roller-tension their sawplates, but instead rely solely on the stiffness of the applied back to prevent buckling. Once again, JD would have wept.

Another benefit of hammer-tensioning, and one Gentle Reader can ascertain easily by examining a saw blade in person (but without the back installed) is that the internal stresses resulting from hammer-tensioning make the sawblade much stiffer than it would normally be without adding metal or weight. Simply remove the back and handle and hold the sawblade out level by one end. A hammer-tensioned blade will sag significantly less than one that has not been hammer-tensioned.

Another easy test for hammer tensioning applicable to panel handsaws is that of bending the sawplate and tapping it with a fingertip producing a musical note that can be varied by changing the degree of bend in the sawplate. In fact, believe it or not, the handsaw was once a popular musical instrument in some quarters in the USA, with all the major saw manufacturers producing specialty musical saws (sans teeth).

In summary, a properly hammer-tensioned saw will be stiffer, will cut straighter, can be made thinner and lighter, and will require less force to operate for the amount of sawdust generated.

The hand-cut and hand-filed teeth of a 210mm Dozuki saw by Nakaya Takijro. The small dings visible near the chin of the blade are the marks left by hammer tensioning.

Teeth

Tooth types and preferences in handsaws vary so widely that little can be said that applies to all. However, Gentle Reader should consider the following when evaluating a handsaw to be used to cut precision joints.

First, assuming the teeth are the desired shape and size and progression, they should be uniformly and extremely sharp, indeed, sharp enough to cut you if touched carelessly. If you place the palm of your hand gently on the line of teeth, you should feel the little buggers trying to grab your skin. Not just one or two of the vicious little teeth should frantically try to eat you, but all of them in contact with your hand should seem to want to take a nibble because each tooth should be either a frightfully-sharp, pointy little knife, in the case of crosscut saws, or a razor-sharp little chisel, in the case of rip teeth. And of course, a well-made saw is always eager to cut anything and everything it can get its teeth into. Just ask it.

Unfortunately, the teeth of most of the new crop of Western saws made nowadays are, in my experience, poorly sharpened and in need of TLC before they are useable. I say this as someone that prefers Western handsaws for some tasks, sharpens his own saws by hand, has purchased, collected and tested both new and antique Western handsaws over the years, and continues to use the better of them regularly.

In the case of most woodworking tasks, sawteeth need to have some degree of set to make the sawkerf wider than the thickness of the plate to reduce friction, binding, and buckling. Indeed, to compensate for a missing taper-grind and hammer tensioning, most modern Western saws are made with excessive amounts of set to compensate. This matters because all the extra wood the sawblade must cut to accommodate this extra set is wasted effort turned into sawdust that does nothing to improve speed or accuracy. Therefore, a good handsaw will have no more set than absolutely necessary to get the job done.

This means, of course, that one needs different saws with different set and different tooth styles for different types of cuts in different types of wood. It makes a difference (ツ)。

On the other hand, if Gentle Reader uses handsaws solely to burn calories, the aforementioned points should all be studiously ignored.

The teeth of a 210mm Hozohiki rip saw hand-forged by Nakaya Takijiro. The hand-filed steel back finished in traditional burnt silk is also visible at the top of the photo. These teeth are specifically designed to meet the demands of professional Japanese luthiers working in exotic hardwoods.

If Gentle Reader is in need of a high-quality hand-forged saw, you may want to consider those made to C&S Tools’s specifications by one of Japan’s last remaining master sawsmiths, Nakaya Takijiro. You can see some of his products at this link.

A 210mm Hozihiki rip saw hand-forged by Nakaya Takijiro from White Label steel No.2. This saw, and especially its teeth, are specifically designed for cutting precision knock-down joints in the hard, exotic woods, such as ebony and rosewood, that Japanese luthiers use to make shamisen, harps, lutes and other traditional musical instruments.

Using a Handsaw to Make Precision Cuts

The overarching guiding principles in using handsaws to make precision cuts are the following:

  1. The Saw: Use a high-quality saw with the features described above. If you don’t yet own such a saw or can’t afford one, and even if you do, educate yourself in blade sharpening, applying set, and in the techniques of straightening sawplates so your saw will achieve its maximum potential performance;
  2. Layout: Layout the cut so there is no confusion about where starts, where it continues, where it ends, and the angle of the cut. Whenever possible mark cuts in such as way that the sawblade can index itself. If there is any chance of confusion, include marks in your layout indicating, for example, the side of the line to cut to and where to stop;
  3. Arrangement: Arrange, support and align the workpiece, your body, and your eye to produce only straight cuts with every single stroke. This point is relevant to item 4 below;
  4. Make of Thyself a Machine: More details below;
  5. Attention: Pay attention to make every single stroke accurate;
  6. Stop & Correct: The instant a stroke goes astray or the cut wanders even a little, stop sawing, figure out why, and make corrections. Not ten strokes or even two strokes later, but instantly. This requires concentration and iron-handed control of your inner badger.

Layout

Spend the time to do layout and marking properly, because confusion and uncertainty during the cut will result in reduced mental focus, and often, poor precision. A solid, well thought-out plan combined with a marking knife and an accurate, hardened steel square help to make good lines yielding good cuts.

Arrangement

In order to achieve No.4 in the list above, “Make of Thyself a Machine,” you should spend the time and develop the habit of securing the workpiece at a height and angle conducive to help an imperfect human body make perfect cuts. In my case, this means checking the angle of the dangle and using a vise, C-clamp or a butt-clamp to hold the wood down. It also means stopping work to rearrange the workpiece when necessary.

In most cases, I like to make gravity my friend by positioning and securing the workpiece so the plane of the cut is vertical. My workbench is level, so a square usually suffices to confirm alignment, but a small spirit level is sometimes helpful too.

For example, when cutting the tails of dovetail joints, I secure the board in a leg vise, and tilt it so the cuts for half the tails are plumb. When done making those cuts, I next rearrange the board in the vise so the opposite sides of the tails are in the vertical plane, and cut them. Perhaps this is overkill, but it is a habit that helps me to consistently make precise cuts with less brain and eye damage.

The body must be aligned with the cut to avoid stresses and strains from misaligning “The Machine.” A comfortable position is therefore necessary.

If at all possible the eyeball must be positioned so it can see both sides of the cut to not only guide the cut, but quickly detect a wandering cut, because we all tend to get lazy partway through a cut and stop looking, allowing our inner-badger to run amok with predictable results.

3 sawyers sawing lumber from a timber, one on top, one from below, and another carrying a saw, probably one he has freshly sharpened. At the right, a carpenter with pipe and tobacco pouch hanging from his waist sash (obi) is using square, sumitsubo, and sumisashi ink pen to do layout on the end of another timber. The mother hens at OSHA would simply be clucking with disapproval if they saw this scene in the flesh.

Make of Thyself a Machine

The title of this section is not intended to suggest Gentle Reader should surgically install bionic parts or change their racial and gender preferences listed in social media to “Tin Person.” (シ) No indeed, nothing so “progressive” is necessary. (BTW, what is the politically-correct pronoun for a cyborg: Clank or clunk?) Rather, this phrase refers to a combination of techniques that will help even non-cyborgs to overcome the erratic tendencies of flesh, sinew and bone in order to produce more consistent, precise results with a handsaw.

To make a straight cut, the sawblade must travel within a single vertical plane during both the cutting and return strokes. While obvious, this is where nearly all people screw up, always when learning how to use a saw, and in most cases, forever. But we can do better.

If Gentle Reader will pay close attention when making a cut with a handsaw, you will notice that the hand, and consequently the saw handle, tend to move in an arc right and left in a horizontal plane as seen from above. This movement is a result of naturally flexible linkage between hand, arm and shoulder that transmits the force generated by the muscles to the tool handle. We must control the limits of this “flexibility” if we are to make a straight cut. We can do this by making of ourselves a “machine.” It’s almost as easy as the “tricky part” of the Big Fig Newton dance.

How to do this? Let’s take it step by step. First, grip the saw firmly but not too firmly. The old swordmaster’s instructions apply: Hold the handle like a small bird: Too loose and it will fly away; Too tight and the little bird will be crushed. This grip is important because if you hold the sword or saw too tightly, your muscles and tendons will lock up and you will be unable to form the consistent machine necessary to accurately motivate the tool.

The second point to understand about grip is that, while all of the fingers of the hand may touch the saw’s handle, apply your gripping force through the index finger and thumb only, such that the saw can almost freely pivot around a line drawn between these two fingers and through the handle.

Next, with the workpiece arranged securely, assume a relaxed stance facing the layout line you will be cutting to on the workpiece. Then, with saw held in the relaxed swordsman’s grip you intend to use during the cut, hang it loosely down alongside your leg. Stand back from the line and adjust your stance so the plate of the hanging saw is in the same plane as the line. This is important: Don’t move your hands, arms, shoulders or hips to align the sawblade with the plane of the cut, but rather move your feet. This is approximately the ideal angle between your body and the intended cut.

Next, without changing position, center your dominant eye on this plane.

Then, being careful to avoid hitting anything (especially stray bench dogs or kitties), gently but freely swing the saw forward and back 90˚inside this same plane. If your hand or your saw touches your leg, or your elbow hits your side, then adjust your stance so they don’t. The saw must swing freely with the sawblade in the same plane as the cut, with your shoulder joint, elbow, wrist and eye all centered on the same vertical plane.

Next, swing the saw up into the cutting position, and move it back and forth as if cutting wood. Your grip should still be loose (remember the little bird), and the saw should continue to move in an invisible plane through your shoulder, elbow, wrist, sawblade, and layout line. Now pay close attention to the movement of your hand as it goes forward and back. It is traveling a little right and left in a horizontal arc? Probably, my cyborg friend.

Now, maintaining the stance established earlier, step forward enough to actually make a test cut. Start with a few itsy bitsy teeny weeny little cuts in a test piece to establish a stable beginning for the kerf. Then begin cutting in earnest, but while doing so, pay attention to the movement of your hand. Is it still scribing right and left horizontal arcs in the air? If it is, then on the cutting stroke, in the case of a Japanese pull saw, or the return stroke in the case of a Western push saw, reposition your stance so the inside of your elbow lightly brushes your side. Then adjust your head and eye to match. This contact between elbow and side is an important target point that will help position one end of each stroke, essentially creating rails for the machine to operate within. Remember the feeling of this contact.

When you make the cut, you will notice the sawblade is still scribing small arcs right or left. This fine movement persists because the wrist joint must rotate slightly to keep the sawblade moving in a straight line, but it is either rotating too much or too little, too spoon or too late, causing the sawblade to deviate from the plane of the cut. It is impossible to reduce this out-of-plane deviation to zero, but you can cancel out most of it by maintaining your swordsman’s grip, loosening your wrist and actively rotating it in anticipation of this right-left arc. Yes, you can do it.

Your shoulder, elbow, flexible wrist and hand, supported by the rest of your stone-stable body, and watched over by your unrelenting Sauron-like eye, now form a machine with invisible rails that will move the saw in a vertical plane almost perfectly aligned in the plane of the line to be cut (perfection is unattainable and unnecessary).

One last point. It is essential to realize that the saw cuts because it is sharp and wants to make sawdust, not because of thy mighty arm, Oh Lord Cyborg. This is another phrase worthy of a forehead tattoo if you have any room left (ツ)。When we actively apply much force to a saw, especially if the teeth are dull, it will resist our boorish behavior, stumble over the woodgrain, clog with the sawdust, and almost always wander out of the plane we want to cut in. To avoid giving offense, please ensure your saw has a true plate and sharp teeth, do your layout, make the machine, start the cut, then get out of the saw’s way, dammit, and carefully watch it make sawdust. Don’t be too proud, Lord Cyborg, because, after all, you are the weak link.

Making the machine takes practice and time, but once you have figured it out, and know how it should feel, you will develop muscle memory. It’s like driving a car: Every modern car is different, but every modern car is the same.

BTW, there are various saw jigs one can make and use to enhance one’s cybernetic capabilities which we will consider in future articles.

Pay Attention

Until the necessary muscle memory has permeated all the way to your bones, don’t forget to pay attention to every single stroke you make with your saw. This is exactly the opposite of human nature that wants to keep on cutting like a badger after a ground squirrel until the cut is finished. But when training oneself to make highly precise sawcuts, it is best to concentrate on each stroke, making sure it doesn’t wander. After all, it is the accumulation of many accurate small cuts that results in an accurate final cut. Likewise, it only takes a few inaccurate cuts to result in a sloppy final cut, so please pay attention.

Once you have made become the machine and developed the necessary muscle memory the process will go very quickly indeed. Sadly, this fine muscle memory is not a permanent thing, but once learned it can be quickly remembered.

Stop & Correct

While sawing away, if you notice your cuts are going astray, stop and figure out why. Is your position good? Is your eyeball where it should be? Is the sawblade aligned with the plane of the cut? Is tension released from your wrist? Is your elbow brushing your side? Is the machine operating faithfully or are the invisible rails bent? Are the teeth dull? Are you applying too much pressure? If things aren’t right, stop the cut, figure out why, and make corrections NOW. Don’t wait.

This self-control is possibly the most difficult task in making accurate cuts with a handsaw, but also the most critical to gaining skill. Failure to do it will result in either learning bad habits, or in delays in correcting the ones you already have. BTW, everyone has bad habits they need to work on, including YMHOS.

The Essential Oilpot

Unlike double-distilled aged-in-fairy-oak unicorn wewe, wood is not a friction-less material. To make things worse, a saw kerf usually becomes “hairy” with loose wood fibers increasing friction in unpredictable ways. And the cherry on top is sap and resin residue found in all wood and which increases friction further.

This friction not only heats the sawblade, possibly warping it and wasting our energy and time, but it makes it more difficult to control the sawblade in the cut, often making our precision suck big donkey donuts. How to counteract this friction? The classical Japanese solution is the Oilpot.

This tool has long had counterparts throughout the world, and it’s as valuable now as it was six thousand years ago. If you want to use handsaws with high precision, you need to make yourself one. You will be impressed with the difference. Nuff said.

The Two-handed Pistol Grip

When I was a young carpenter working commercial construction, I had a foreman named (I kid thee not) Jack Frost who was offended that God did not give him a tail, especially when working on high scaffolding. Gentle Reader may agree that a fifth appendage could often be handy, despite the fashion compromises it would “entail.” However, consistent with human physical limitations, the fact remains that most joinery saws are operated using either one hand or two, but not by tails.

The discussion above is relevant to all saw grips, but is focused mostly on the single-handed grip. However, just to be thorough, your humble servant would like to describe another style of grip used by some Japanese craftsmen, one your humble servant calls the “Two-handed Pistol Grip.” As the name suggest, instead of gripping the saw in one hand off to the side of the body, the saw’s handle is gripped first by the dominant hand in a pistol grip with the index finger extended along the handle’s side. The index finger of the off-hand is then extended alongside the grip parallel to and opposite that of the dominant hand, and the remaining fingers wrapped over those of the dominant hand.

The sawblade is then operated inside a plane going through the chest and centered on the user’s nose, quite effectively counteracting the right-left arc tendency. The “little bird grip” is essential to using this technique effectively.

This technique is not good for powerful cuts, but works well for shallow, precise cuts.

I apologize that, despite popular demand, this article lacks clean diagrams and pretty pictures of your humble servant exhibiting these techniques while wearing his sexy blue sequin bikini and famous aluminum foil alien mind-ray dispersal cap (with curly copper wires and red fringe). But, as the saying goes, “Life is a bowl of cherries, mostly pits.”

Until we meet again, I have the singular honor to remain

YMHOS

Another construction jobsite non-compliant with OSHA rules.

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Japanese Handplanes: The Kiwaganna Skewed Rabbet Plane

I made myself a snowball
As perfect as could be.
I thought I’d keep it as a pet
And let it sleep with me.
I made it some pajamas
And a pillow for its head.
Then last night it ran away,
But first it wet the bed.

Shel Silverstein

In this article your humble servant will introduce a Japanese plane called the Kiwaganna, meaning “skewed rabbet plane.”

This is an important handplane in common use in Japan, although not well known in the West. But there are enough people who own this tool and who struggle mightily to master it, that an explanation of some of the solutions your humble servant has learned over the years from senior Japanese craftsmen, and acquired during many decades of brutal study at the University of Stoopid, School of Hard Knocks (Lower Outhouse Campus), may prove useful.

What is the Kiwaganna Handplane?

The Japanese Kiwaganna is written 際鉋 in Chinese characters, and pronounced kee/wha/gah/nah. “Kiwa” means “edge” or “verge,” and “ganna” means handplane.

While the design of the Japanese version is unique, as far as your humble servant is aware, many other versions exists around the globe. This plane can handle a number of tasks, but it specializes in planing a straight-sided groove or rabbet right up to an edge or line with a clean 90˚ inside corner. A common application is planing the tongue around the perimeter of a board to make the bottom of a drawer, or a panel in frame and panel construction.

The skewed blade found in the kiwaganna is also not unique to Japan, but the Japanese version has some advantages, including simplicity, rigidity, and reduced weight.

In general, a skewed blade in a rabbet plane provides two benefits. The first is that the reaction forces pushing back on the blade include a vector that tends to push the plane towards the line, edge, inside corner or verge being planed to, making the plane more stable in the cut, an important factor where precision is necessary.

The second and most important benefit of the skewed blade is the smoother cut and reduced tearout it makes possible, especially important when planing cross-grain.

The other benefit the skewed blade provides in the case of the Japanese kiwaganna is the point of the skewed blade penetrating the body of the plane and ending flush with the side of the body, making possible a zero-clearance cut to a line without the extra weight and cost of complicated mechanisms and reinforcing plates. It’s a deceptively simple but clever design.

Craftsmen who use kiwaganna typically own a two-piece set comprised of a right-hand and left-hand version to deal with tight access and changing grain direction. But the right-hand version is the most popular by far.

This plane is of course used by joiners, cabinetmakers, sashimonoshi and furniture makers, but you would be surprised at how popular it is with carpenters and timber framers for cleaning the 90˚ inside corners of joints such as tenons.

Points to Keep In Mind

While a simple tool, the kiwaganna often proves frustrating to first-timers. Indeed, your humble servant struggled with kiwaganna for far too long before he figured them out. To avoid similar damage to brain and ego, Beloved Customers that wish to become proficient in using this elegant tool will find it useful to understand the following nine points.

1. First, a brief inspection of the body and the cuts made to receive the blade will show that kiwaganna dai (body) are more fragile than that of regular hiraganna planes, so when adjusting the blade, please use a wooden, plastic or rawhide mallet, not a steel hammer.

2. When removing the blade, strike the dai at the same angle as the blade is inlet into the dai to reduce unnecessary stresses. This means you will hit the top corner of the dai on the side opposite where the blade’s point exits. Clip off and round over this corner of the dai with a knife or chisel to prevent your mallet from chipping the dai. Striking the opposite corner can have bad results.

3. The right and left side edges of the blade must fit the retention grooves tightly where they exit the top surface of the dai. If the fit is too loose, the blade will be difficult to keep in alignment, but if the fit is too tight the blade may crack the dai during seasonal shrinkage. Older dai are usually safe, but a plane shipped from a wet Tokyo summer to a hellishly dry Arizona may experience problems. This article provides more details about fitting the body to the blade.

When shaving the grooves, work very slowly and carefully. Color the blade’s side edges with pencil lead or marking pen ink. Insert it into the grooves and note the high colored areas. Shave these down just a tiny tiny bit with a very sharp chisel, then insert the blade and check. Repeat as necessary. Don’t create a big gap between the walls of the groove and the sides of the blade (versus face and underside of the blade which must be tightly pinched in the grooves), just make sure the blade is not wedged tightly between the grooves.


4. Sharpen and polish the blade and uragane (chipbreaker) well and make sure they fit each other tightly without a gap near the cutting edge. The skewed nature of the blade and chipbreaker make this difficult to judge, so exercise caution. In many cases, the plane will work just fine, and maybe even better, without its uragane. The uragane has a bevel ground into its pointy corner. Make sure this is not touching the dai when inserted properly. Keep in mind that you will need to periodically grind this bevel down after sharpening the blade every few times or it will touch the dai creating a restriction where shavings will become jammed. When you sharpen the blade, you will also need to resharpen the uragane too to ensure they match each other tightly. Not every time, but once in a while. A lot of people fail to maintain the uragane and then wonder why they stop working.

5. Check that the “ear” of the blade (corner at the cutting edge opposite the pointy corner) is ground back enough so it is not inside the groove, because if it is, shavings will become jammed.

6. Contact between the back of the blade and the block should not be too high-pressure, otherwise the area on the sole behind the mouth may be pushed out making the plane misbehave, a common problem with this plane. You want even pressure to ensure the blade is stable, but remember that it is the grooves pinching the blade that keeps it in place, not pressure on its back.

7. With the blade fitted to the grooves and most of the pressure relieved from its back, insert the blade. Check that it projects evenly from the mouth its full width. This is very important. If it projects further on one side than the other, resharpen/reshape the cutting edge so it projects perfectly uniformly. This uneven projection is almost always the result of inattentive sharpening. Besides projecting uniformly from the mouth (when the sole is at the mouth is perfectly flat), the point of the blade must penetrate the dai (body) and be flush with the outside surface of the sidewall. Failure to get these two subtle details right is the most common cause of failure to perform in the Kiwaganna plane.


8. The mouth opening, in other words the gap between the blade and the sole of the dai where it exits the dai, must be narrow, and even in width, but not closed or skewed, otherwise shavings will jamb in the mouth, another common problem with kiwaganna. If the mouth is not even, use an adjustable steel protractor to match the angle of the blade measured from the side of the dai where the point of the blade exits. Remove the blade and mark the mouth with a sharp marking knife so the mouth is exactly the same angle as the blade. When doing this layout, be extremely careful to make the mouth opening of uniform width to match the cutting edge, but keep the mouth as narrow as possible. Use a sharp chisel to cut to this line making the mouth perfectly uniform. Insert a thin knife blade or sharpened utility knife blade) into the mouth to shave and clean it after chiseling.


9. There is nothing wrong with leaving the sole perfectly flat instead of having hollowed-out areas typically added to standard hiraganna planes. Just make sure it is truly perfectly flat. I have no problem with using sandpaper on float glass to true the sole of a kiwaganna, but a card scraper is a better tool for the job.

Juggling Blades

Although we addressed them above, let’s review the two critical factors you must juggle to keep a kiwaganna working well. I’m repeating these points not because I doubt Beloved Customer’s intelligence, but only because repetition improves understanding.

First, maintain the angle of the blade’s skew so that it projects a uniform distance from the mouth (with the mouth/sole flat and true). To do this you must pay more attention when sharpening the blade than is normally necessary. If you get this wrong, nothing will go right.

Second, as mentioned above, to cut into the corner of the rabbet cleanly, the point of the sharpened blade must penetrate the sidewall of the dai and be perfectly flush with the sidewall but without projecting out past the sidewall when the blade is projecting the right amount from the mouth and uniformly across its width. If the skew of the blade is wrong, or the dai is warped or worn, this point will end up being either recessed inside the sidewall or projecting outside it. It needs to be flush with the sidewall. If it is not, you may need to either shave material from the side of the plane (not recommended) or grind down the side edge of the blade near the point, a drastic measure. This is seldom necessary, and when it is, the reason is almost always a badly warped dai.

As you can see, this is a juggling act, but so long as you focus on these two points, and maintain the proper skew angle, all the blades will remain spinning in the air grinning from ear to ear.

YMHOS

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, thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may my kiwaganna planes all warp to resemble mushy bananas.

Specialty Joiner Chisels: The Sokozarai Nomi

底さらえ鑿の一分五厘 : 日々の製作と研ぎの記録 ~木工 藤原次朗のブログ~

Quality is not an act, it is a habit.

Aristotle, 384–322 BC

In this article your humble servant will introduce a standard woodworking tool which I believe to be unique to Japan, although I have no doubt individual craftsmen around the world have produced versions of it for their own use for hundreds, maybe thousands, of years.

I will explain the jobs this tool is used for, how it is used, how to fettle it, and how to sharpen it. I will also share some first-hand business insight regarding why Japanese women make this tool essential to the joiner in both performing traditional joinery in Japan, as well as the sometimes challenging task of getting paid for his work.

Mr. Spock will also make a brief contribution to the discussion.

Definition & Pronunciation

The Sokozarai Nomi (pronounced Soh/koh/zah/rahi noh/me and written 底浚い鑿 ) translates to “bottom-cleaning chisel.”

It is a simple tool consisting of a differentially-hardened steel shaft, with a small, short, sharp foot formed at the end, attached via a tang to a wooden handle, and secured by a conical ferrule.

The Sokozarai chisel is one of three specialized chisels used specifically for joinery work. Cabinetmakers and furniture makers use it too. Two other specialty joiner chisels are the “Mori Nomi,” which translates to “harpoon chisel,” and “Kama nomi,” which translates to “sickle chisel.” Perhaps we will discuss these in a future article.

A larger version of the sokozarai chisel is used for cleaning the bottom of the larger mortises commonly cut in timber frames.

The Role of the Sokozarai Chisel

The sokozarai chisel is used for two purposes. The first is loosening and removing chips from inside mortises. One simply hooks the offending waste with the chisel’s toe and flips it out. 

The second role of the sokozarai chisel is to flatten and even plane mortise bottoms. When set up correctly, it will cut shavings from the bottom of mortises cut in softwood planing them flat and clean.

Indeed, in advanced joinery work, a skillful joiner will plan and execute his joints such that the material left remaining at the bottom of a mortise cut into a stile intended to receive the tenon from a rail is less than 1mm thick, thin enough to allow light to pass through. The ability to routinely cut joints like this, without cutting all the way through, is a mandatory skill of the professional joiner.

I suspect that about now Gentle Reader is forming his elegant eyebrow into an artistic and skeptical arc as he ponders why one would go to the trouble of making clean and pretty the bottom of a hole upon which no one will ever gaze, leaving a paper-thin wall of uniform thickness at the bottom admitting light into a space no one will ever see. Can there possibly be method to this madness? Welcome to traditional Japanese joinery.

Consider that a rough, bumpy floor in a mortise prevents the tenon from seating the last few millimeters, but by planing it flat with a sokozarai chisel, those last few millimeters can be converted to useful space to house maximum-length tenons ensuring maximum resistance to withdrawal and bending forces resulting in strong, slender but durable joinery without adding extra weight. This is a big deal in the case of the slim, flexible frame members found in operable traditional Japanese joinery such as shoji, itado and tsuitate screens, joinery that must satisfy the severe eye and meet the high standards of fit and finish expected by many Japanese women, the most unforgiving consumers in the world.

I don’t know when this detail entered common use, but as Gentle Reader is no doubt aware, the older and more common type of mortise and tenon joint found in joinery worldwide is the through single or double tenon with the tenon’s end exposed at the rail where it is often wedged, a technique that is undoubtedly stronger.

On the other hand, the fully-housed tenon made easier to fabricate using the sokozarai chisel has two advantages over its older, less-refined brother the through-wedged tenon. First, it simply looks better and more elegant when new, and is therefore better able to survive the strict final inspection by the lady of the house thereby more reliably earning the reward of final payment. Hallelujah, pass the bottle brother!

Second, it simply looks better to the eye and feels better in the hand as time goes by because, as the stile shrinks during drier months, the once flush end of the through-tenon won’t project past the surface of the stile creating an unslightly, uncomfortable bump, and during the wetter months it won’t recede back into the mortise leaving an indentation in the stile and an uneven appearance.

These details are not based on esoteric imaginings about quality, but are make or break business decisions essential to avoiding complaints from the same unforgiving Japanese women. And of course, in a country where advertising and representations are routinely and intentionally false (sad but true), word of mouth among sharp-eyed quick-tongued women is critical to a craftsman’s success. Please note that I say this as someone who has has been married to a Japanese woman for 43 years, has lived and worked in Japan for over 30 years, and during those 30 years has had plenty of direct commercial experience working with Japanese women as both customers and team members.

Next time we are sharing a cup of hot cocoa around the evening fire, remind me to tell you the story about two stressful days spent inspecting Thassos marble slabs for a new building’s lobby walls in the company of three Japanese women: an Architect, a Quantity Surveyor, and a Project Manager. All the story lacks is a Rabbi and a Priest to make a rib-splitting joke (ツ)。

A 4.5mm differentially-hardened sokozarai chisel with red oak handle

Using the Sokozarai Chisel

To use the Sokozarai chisel, and assuming you are right-handed, hold the handle in a fist in your right hand with the blade projecting from the bottom of the fist. Lay the back of your fingers on top of and crosswise to the long direction of the mortise. Insert the blade of the chisel into the previously cut mortise hole and press the back of the blade’s neck (opposite the cutting edge of the foot) against the outside edge of your forefinger. Then pinch the blade’s neck between your thumb and forefinger. This is the grip.

To remove loose waste, insert the sokozarai chisel into the mortise hole and move it around gathering chips on the chisel’s toe. Then pull the chisel up and out of the mortise quickly to pop chips out.

To cut loose chips still attached in the mortise hole, press the chisel’s foot to the bottom, move it forward until it snags on irregularities, then rotate the handle towards your body using your forefinger as a fulcrum to lever waste out.

To shave the bottom, simply move both hands forward with the bottom of the foot parallel with the intended bottom of the mortise. Developing a sense of the chisel’s action will take practice. Shining a flashlight into the mortise frequently at first will help develop these senses.

To check the depth of the mortise, a specialist kamakebiki, essentially a small router plane, is ideal. But you can make a simple depth gauge by sharpening the edges of the head of a nail or drywall screw, driving or screwing it into a small block of wood, then cutting off and filing the point to avoid ouchies. Using this, you will be able to detect bumps and irregularities remaining on the bottom. Indeed, it too can be used to shave the bottom, but it won’t clean all the way into corners unless you grind the head square or rectangular.

For advanced work, make a slightly undersized test stub tenon with shoulders from hardwood the depth of the finished mortise, and anoint the end with cheap dark lipstick or Vaseline with black oil pigment mixed in. High spots remaining at the bottom of the mortise will be highlighted. With practice, you won’t need this test tenon, but you will still definitely need a sokozarai that is sharp enough to plane the bottom.

Next, let’s consider how to prepare a new sokozarai chisel.

Fettling the Sokozarai Chisel

Unlike most other Japanese chisels, the Sokozari chisel is not laminated construction, but is formed of one piece of differentially-hardened high-carbon steel. Differentially-hardened in this case means that the foot and lower 1/4 of the leg’s length are hardest, becoming progressively softer going up the leg until it is dead soft at the tang. This means the cutting blade, (what your humble servant calls the “foot”) of this chisel will become sharp and stay sharp, but the neck is left softer so it will not snap off, and can even be bent a little to adjust the angle of the foot if necessary.

Low-quality sokozarai have both soft shafts and feet.

Flatten and Polish the Foot’s Bottom

The bottom of the foot needs to be flat and polished, but because of this surface’s narrow width and short length, it can be challenging to accomplish without rounding it over or skewing it.

It often helps to grind a hollow into the foot’s bottom the thickness of a nat’s eyebrow to help speed up the flattening and polishing process. If you use a grinder, be very careful to avoid overheating. It should take no more than one or two brief touches to the wheel.

When flattening and polishing the foot’s bottom surface on diamond plates and stones, it also helps to make a guide block. Cut a slot in the side of a small block of hardwood to house the bent shaft with the bottom of the foot located flush with the block’s bottom surface. Lock the shaft into the guide block with a wedge or a clamp to stabilize it. 

The jig in the photos above was made by a Most Beloved Customer who does exceptional high-quality joinery work.

An alternate sharpening jig can made by cutting a crosswise groove, similar to the one shown in the photo below, into the top surface of a stick of scrap wood, perhaps 50mm wide, 200mm long and 20mm thick. The bottom surface of the foot should be almost, but not quite flush with the stick’s edge, projecting the thickness of a piece of paper. Secure this jig to your workbench with a clamp or in a vise, press down on the blade with one hand, and move a sharpening stone along the side of the jig over the foot.

This guide block rides directly on the stone as you flatten and polish the foot’s bottom. Don’t let the foot’s bottom get skewed or rounded over. Work slowly and check constantly. This is a one-time operation.

Once the bottom is flat and polished, you should only need to polish the bottom of the foot on your finishing stone.

Adjust and Polish the Cutting Edge’s Bevel

The bottom of the foot is now flat and pretty, but the angle of the cutting edge is usually still far too steep, and the bevel’s surface is rough. This must be corrected.

Modify the cutting edge’s angle by grinding the bevel on a diamond plate. The final angle you chose for the cutting edge will depend on your preferences and the wood you will be cutting. Steeper angles are more durable. Shallower angles cut better, but dull quicker. 20~24 degrees is usually OK. When I was a young man, I knew professionals who took the bevel angle down to 15 degrees. 

You may want to make another narrower guide-block clamping 90 degrees across the the shaft to help hold/stabilize the blade during this operation. When you have adjusted the angle to where you want it to be, then polish it on your sharpening stones. Be careful to avoid skewing it or rounding it over. You want sharp, clean corners.

To routinely sharpen/polish the bevel, hold the chisel in one hand with the bevel face-down on the long side of your sharpening stone. While stabilizing the blade and applying pressure on the bottom of the foot with a fingertip, move the sokozarai chisel back and forth in small strokes being careful to avoid rocking it and rounding it over.

Adjust the Foot’s Length

This step is unnecessary for most applications, but I will touch on it just to be thorough.

The length of the foot is fine as-is for most furniture mortises, but for very tiny mortises as in screens, light fixtures, and small casework, the foot may need to be made shorter. It is not unusual for a tategushi or sashimonoshi to own multiple sokozarai nomi with feet and shafts of different widths and lengths and bevel angles to clean the mortises he makes the most.

Please note that the mortise holes for kumiko members installed in shoji screen and most other types of latticework are shallow and do not require the strength of long tenons, so the mortises are usually cut using mori nomi (harpoon chisels) with a hook on the end to pull out waste quickly, and the bottoms are left rougher.

Conclusion

Beloved Customers that have purchased our chisels, and diligent Gentle Readers that have read this blog, are aware that your humble servant insists our chisels not be used to scrape or lever waste out of joints. The reasons for this are my desire for Beloved Customer’s most excellent chisels to remain as sharp as possible as long as possible, and to avoid chipping the cutting edge. They are, after all, refined cutting tools with sensitive feelings, neither thuggish prybars nor pot-metal screwdrivers.

The Sokozarai chisel was invented specifically as a partner to chisels used for cutting the clean mortises essential to Japanese joinery, and to protect the super-sharp cutting edges of those chisels from damage resulting from barbaric treatment. I encourage you to level-up your joinery skills by procuring and using one. You will be glad you did.

And so I wave farewell until the evening we share a cup of hot cocoa around the irori fire. In the meantime, I am humbly grateful for the honor to remain,

YMHOS

Adieu for now, Gentle Reader!

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 by using the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may my sokozarai chisels get athletes feet!

The London Finish

A 70mm handplane with a blade by Nakano-san and body by Inomoto-san with a London Finish

A person who never made a mistake never tried anything new.

Albert Einstein

here are more ways to finish wood than there are to cook beans, but unlike the musical fruit, this finishing technique became famous through the products of London’s elite gunsmiths such as Durs Egg (Est. 1772), John Rigby & Co (Est, in Dublin in 1775 and moved to London in 1866), Joseph Manton (1766 – 1835), Boss & Co (Est. 1812), James Purdey & Sons (Est. 1814), Holland & Holland (Est. 1835), and a hundred other European gunmakers. However, the technique actually pre-dates the 1700’s by many centuries.

The Ancient London Finish

While the traditional London Finish got its name from the justifiably-famous products of the high-end London gunmakers, some of the most famous of which are named above, it was a technique used to seal and finish high-quality woodwork since ancient times in all countries where the source of linseed oil, namely the stringy plant called flax, grew.

The difference between the linseed oil widely used for cooking, paint production, and woodworking and the flax seed oil sold as a health product in the West nowadays is simply the method used to extract oil from the flax plant.

Of course, Gentle Reader is no doubt aware that the fibers of the cotton plant have been used to make textiles since at least 6,000 BC, but what you may not realize is that it was rare and so labor intensive to produce that at times it cost more than silk in the West, as recorded in tax records of the time. Indeed, it wasn’t until the invention of the Cotton Gin in 1793 that cotton textiles became affordable for ordinary people. My point is that linen cloth made from the fiber of the flax plant, and woolen cloth made from animal hair, were the most common types of textile available. Indeed, flax can be grown in even poor soil, and can be spun and woven into useable thread and cloth in small lots in most any home, so “homespun linen” was once the cheapest most widely-used textile available worldwide, used for everything cloth is nowadays, and linseed oil was an ordinary by-product of flax production.

The London Finish made famous by the gunsmiths of Olde Londinium consisted of many coats of boiled linseed oil, with some added dryers, forcefully rubbed into the wood by hand (the bare hand, as a matter of fact), allowing days and weeks between coats for the oil to partially polymerize. Indeed, this is the source of the term “hand-rubbed finish” furniture and cabinet companies everywhere lie about applying. If you have a free month, please give it a try.

This finish was also used for furniture and cabinetry since ancient times as referenced in books of the era which is probably why some modern woodworkers, ignorant of chemistry and eager to employ historical techniques, still soak their projects in linseed oil potions.

While the final product of the traditional London Finish is indeed subtly beautiful, it takes a long time to accomplish, it’s expensive, it does little to prevent moisture from moving in and out of the wood (and therefore allows the wood to expand and contract with varying moisture content rapidly), and it does little to protect the wood from damage. Other downsides include the fact that linseed oil gives a yellow cast to wood, which gunstock makers and other woodworkers historically compensated for by dying the wood slightly red using alcanet root. Also, linseed oil never fully solidifies and so attracts grime, eventually oxidizing and turning black forming a “patina” many people admire without realizing its dirty nature.

The Modern London Finish

The wood finishing technique described in this article is a modern, improved version of the traditional London Finish developed by American custom gunstock makers. I learned about it when I was looking for a better finish for the stocks I made for my own smokepoles, everything from flintlock rifles and pistols to large-caliber bolt-action rifles. Through applying, using and comparing the long-term results of both the traditional linseed oil London Finish and this modern version, I came to treasure the modern version’s durability and effectiveness at moisture control. Soon I was using it for everything from tool handles to furniture and casework with excellent results.

What the top American custom gunstock makers that developed this finishing technique were seeking was a method that eliminated the stinky, yellowing, dirt-magnet, spontaneously combusting linseed oil, with something quicker to apply, more durable, and more protective. The result is the finishing technique described herein. BTW, nowadays British and European custom gunstock makers use it too.

The primary difference between the Traditional and Modern London Finish is that the traditional technique relies heavily on traditional linseed oil, a product that does little to protect wood, while the modern technique relies on modern varnish or polyurethane, but with a twist.

Where the two finishes are alike is that neither are surface finishes, but are soaked into the wood’s fibers. By contrast, normally-applied varnish or PU finishes are film finishes that, while they may adhere to the wood well when fresh, do not penetrate deeply, but remain on the surface where they quickly degrade due to UV light exposure, and shrinkage. Eventually and unavoidably their bond with the wood they are tasked to protect or beautify always fails, usually sooner than later, whereupon it stops doing its job.

The modern London Finish soaks into the wood’s fibers where it hardens, and is protected from UV and shrinkage damage. It also fills the wood’s pores sealing them long-term and forming a smooth, flat surface free of the dents and streaks at the wood pores that always develop when shrinkable varnish or PU are applied as a surface finish. Most importantly, it seals the wood with a durable material that cannot be removed without actually carving or abrading the wood away, protecting it from moisture/dirt/oil intrusion. This makes it a better and more attractive long-term finishing solution, one that, unlike the traditional London Finish, doesn’t need to be refreshed annually.

Next, allow your humble servant to present the performance criteria I consider important when selecting a wood finish for tools.

Performance Criteria

The following criteria are focused on improving the longevity, durability and stability of the wooden components of handtools used in woodworking. These include the wooden bodies of handplanes, and the wooden handles of chisels, axes, hammers and gennou.

So what do we need a finish used in these applications to accomplish?

  1. Stability: Minimize moisture movement into and out of the wood cells due to humidity changes, perspiration and rain thereby reducing the swelling, shrinking and warpage of the wood. This is specially important for handplanes, gennou handles, and some types of furniture and cabinetry. A surface finish that quickly oxidizes, suffers UV degradation, becomes inflexible and suffers shrinkage cracks or is easily chipped and/or abraded won’t get the job done for long.
  2. Protection from oil and dirt: Prevent dirt, dust and oil from the user’s hands or the environment from penetrating below the wood’s surface keeping it cleaner. To accomplish this a finish must both fill the ends of open cells exposed at the surface with a water-proof, non-shrink plug (a “filler”) and seal the cells with a waterproof and oil-resistant chemical binder.
  3. Insect and Bacteria Protection: The finish must lock away the yummy smell of raw wood so bugs will go beetling on by without stopping to snack, set up house, or lay eggs. It must also prevent bacteria spores, nasty things always present in dirt, from taking root.
  4. Appearance: A smooth surface that looks like wood, not plastic or varnish.

These are only your humble servant’s criteria, of course; Your needs may vary.

Why Is the Expansion, Contraction and Stability of a Wooden Tool Component a Concern?

Trees are water pumps. Evaporation at the leaves sucks water, and with it, dissolved chemicals up from the ground. After a tree dies, most of the water contained in its cells migrates out of the wood, the individual cells shrink in size and crinkle as they dry, and the cell walls become stiffer and much stronger. However, despite its transition from flexible, moist, growing plant to stiff, dry board, left as-is a dead wood cell does not abandon its God-given duty to pump water but will faithfully continue to absorb and expel water, albeit to a more limited degree than when it was alive and kicking, causing its dimensions to shrink and swell in response to changing moisture conditions in the surrounding environment.

The problem is that the rate water enters or leaves the wood cells varies with a number of factors. One such factor is the location of the cell within the block of wood, producing differential expansion/shrinkage along with stresses and warpage. Most importantly, end grain absorbs and releases moisture much more quickly than side/face grain does. Slowing down the rate of water gain/loss is important to minimize and equalize internal stresses and to keep a wood product stable.

Besides the natural seasonal changes in humidity, modern air conditioning and heating equipment can create wild swings in local humidity, causing wooden components of furniture and tools, such as the bodies of Japanese handplanes, to warp, harming their ability to plane wood as intended. When this happens, and it will, time and effort is periodically required to adjust a wooden-bodied plane’s sole. This can be frustrating. Short of using a vacuum pump to suck heavy hardening resins into a board’s cells, it is nigh impossible to entirely prevent moisture from entering and leaving wood with changes in environmental humidity, and the dimensional changes, internal stresses, and warping that results.

In the case of a wooden-bodied plane, both ends and the surfaces inside the hole cut for the blade have exposed endgrain which absorbs and releases moisture quicker than side grain, so that when the humidity of the surrounding air increases, airborne water penetrates the endgrain faster than the sidegrain, and the endgrain surface at the body’s ends and inside the mouth swell first, causing dimensional changes and differential stresses, and often, warping.

By reducing the rate of absorption of moisture by the endgrain fibers to more closely match that of sidegrain fibers, swelling, shrinking and warping can be reduced. This is where the London Finish shines.

Since learning this method, I have used it not only on my guns, but also on timber frames, doors, tools, workbenches, furniture, cabinets, chests, tansu, tsuitate, and other wood products with excellent results. 

A note about so-called “Danish Oil” finishes is called for. Danish Oil is boiled linseed oil combined with thinners, dryers, and varnishes. It polymerizes much quicker than simple boiled linseed oil, and is much easier to apply. By itself, varnishes and polyurethanes will not soak far into the pores of the wood (xylem tracheid), but by reducing its viscosity with linseed oil and thinner, the liquid will soak further into the grain and pores before more-or-less hardening. While superior to plain BLO (boiled linseed oil), Danish Oil is still not effective at either preventing water migration, or protecting the wood from dirt and oils. And besides, it stinks and starts fires. 

A gennou hammer with a Kosaburo head and black persimmon handle with a London Finish

Applying the Modern London Finish

This technique requires only a few inexpensive materials, and no equipment of any kind, but it does take some time and effort to apply.

Tools and Supplies

You will need the following tools and supplies:

  1. Clear varnish or polyurethane finish in a can. Gloss finish is fine, but I prefer a satin finish. Minwax PU works well, while Epifanes is best.
  2. Thinner or mineral spirits. Not the water/acetone/oil-based low VOC crap sold at home centers. A professional-grade thinner from a Sherwin Williams store or other specialist paint store selling professional-grade materials is best.
  3. Mixing container the size of a soup can or jam jar with a lid.
  4. Small paintbrush, perhaps 3/4″ wide. Cheap is fine.
  5. 320 grit and 600 grit wet-or-dry sandpaper.
  6. Clean rags,
  7. Brown paper from shopping bags
  8. Latex/rubber gloves to keep finish mixture off hands. It can get messy.
  9. Masking tape.

The Finish Mixture

The finish mixture to be used is the varnish or PU you selected thinned 100% with thinner. You won’t need much to complete a few plane bodies or tool handles, less than half a soup can in fact, and it’s best to use in small batches. The lid will keep it from hardening between sessions. It’s not a lot of work, but with drying time, the process may take five or six days.

The Steps in Finishing a Wooden Handplane Body or Tool Handle

1. Remove the blade and chipbreaker. Tape the chipbreaker retention rod with masking tape. In the case of gennou handles, tape the entire head except the eye. For chisel handles, tape the ferrule, crown and the end of the handle (you don’t want the finish mixture to soak into the end of the chisel handle because it will make the fibers too brittle.)

2. Apply the finish mixture to the end grain at the plane body’s ends and all surfaces inside the mouth. In the case of hammer/gennou handles, apply it most heavily to the butt and eye. Apply it heavily, frequently, and forcefully to encourage the wood to soak up as much as possible. Repeat until the wood won’t soak up more. This is the step that matters most. Apply to all other surface of the dai as well. Allow to dry overnight. There’s absolutely no need to put any effort into making it pretty at this stage.

3. Repeat Step 2.

4. Apply another coat of finish mixture, and using small pieces of 320WD paper with fingers and sticks, wet-sand all surfaces thoroughly. The goal is to produce a fine slurry of finish mixture and sawdust, and to force this deeply into the wood’s grain, especially end-grain, clogging them solid. Don’t sand the area in front of the mouth hard enough or long enough to remove material, change its shape, or round over the corners, though! This is extremely important. This slurry, combined with the varnish/PU already hardened in the wood’s pores, will serve to drastically slow down moisture movement once it sets. It won’t stop it entirely, but it will moderate it more than spindle oil, linseed oil or Danish oil ever could, and it won’t crack or flake off leaving the wood unprotected. Don’t wipe off the wet slurry, but leave it standing/smeared on the wood’s surface and let it dry overnight. It will look terrible for now, but never fear for tis all part of a cunning plan (ツ)!

5. Apply another coat of finish and wet sand with 320 grit WD paper again making sure to hit all the places you might have missed before and knocking down any hardened slurry from step 4. Allow to dry overnight.

6. Wet sand with the finish mixture using 600 grit WD sandpaper this time. Be sure to sand down and completely and thoroughly remove any hardened finish or slurry remaining on the wood’s surface. This is important. After sanding, but before the mixture hardens, scrub it down with clean rags and/or brown paper from shopping bags to remove all remaining finish from the wood’s surface. Allow to dry overnight. You may need to repeat this step for best results.

7. The next day examine the wood’s surface for any remaining finish/slurry visible on surfaces. Remove any you find with 600 grit WD sandpaper and the mixture.

8. Allow to dry for 24 hours.

9. Scrub with brown paper from a shopping bag.

10. Apply automotive carnuba paste wax, and polish out.

Remember that, if applied correctly, the London Finish as described herein should not create interference or change tolerances in the tool because there shouldn’t be any finish material left proud of any of the tool’s surfaces to cause interference.

When finishing the blade retention grooves, you will find it difficult to sand up inside them with your fingers, so use sticks. But don’t remove much material in creating a slurry or the blade may become too loose. And be sure to remove any and all slurry or finish that remains on the wood’s surface.

At this point in the process, the London Finish is complete. It is well suited, in my opinion, for guns, tools, workbenches, doors, timber frames, as well as any furniture or casework where protection is desired but a surface finish is not desired. This finish also works well for carved wooden surfaces, but with less sanding. It also has the distinct advantage that it does not require careful application, so if brush hairs or sawdust get caught in the finish, or bubbles or sags develop, never fear, because they are all going to be wet-sanded away. If you decide to apply a final surface coat, however, then greater care is necessary for the final coat.

If you are doing casework or need an attractive surface finish, a topcoat or two of the same mixture, freshly made, applied with a clean brush is just the ticket. If a really nice finish is desired, several coats can be applied, wet sanding between each, and finally polishing with polishing compound (automotive paint supply houses carry this in many grits) to create a mirror finish.

If you feel brave enough to tackle large surfaces, such as a tabletop where this finishing technique excels, some time and effort can be saved by using a pneumatic or brushless random orbital sander. The type of motor matters because you don’t want a spark to ignite the thinner when wet sanding. You have been warned.

A quick note on frame and panel construction is warranted at this point. If possible, it is best to apply the finish (any finish for that matter) to all surfaces of panels, especially endgrain, before gluing them into their frames. In any case, a bit of paste wax (I use beeswax-based Briwax) applied to the inside of frame rabbets and the edges of panels before assembly will prevent finish from accidentally gluing the panels into the frames, thereby restricting expansion and contraction, and eventually producing cracked panels.

An 80mm handplane with a blade by Yokosaka-san and body by Koyoshiya with a London Finish. If it looks as if no finish at all has been applied, that’s because there is no film finish on the wood’s surface to be seen.

The Story of Why I Started Using the London Finish for Plane Bodies

Back in 2010 I was transferred from Orange County in Southern California to Tokyo, Japan. Due to an error by the moving company, most of my beloved tools were left behind in a storage unit In Las Vegas, Nevada, placing my sanity at imminent risk. I bought replacement chisels and planes (hiraganna, mentori, shakuri, etc) in Tokyo at that time. I had become dreadfully tired of the warpage that often developed in my plane bodies each time I moved, so I considered ways to reduce this nasty tendency, and of course, tried the London Finish I had been using on my gunstocks back in the USA. The results were perfect.

After applying the London Finish to them in Tokyo, I used them for about a year through all the seasonal humidity changes common to Japan and exposed to indoor heating and cooling. They stayed straight the entire time. My job then transferred me to the island of Guam, with high temperatures and constant 85% humidity, where I used and stored these high-quality planes in a hot and humid garage for 1.5 years. They still stayed straight. When I returned to Tokyo, my wooden bodied planes again made the 35 day land and sea voyage inside a hot and humid container. They arrived at their new home straight. At the time I am writing this, those same planes have been in my home here in Tokyo for over 8 years through the various seasons and humidity changes, and have mostly remained straight.

Not having to regularly true the soles of my wooden planes since then has saved me a lot of time and headaches (as he is wont, Murphy carefully ensured that they warped and stopped working at the most inconvenient time possible), and of course has extended their useful life.

Another special benefit in my case is the resistance the finish has to sweat, oils, acid and dirt from my hands, which, in my case, causes white oak to turn black almost immediately. This is doubly true in the case of my chisel and hammer handles.

I have taught this method to many people that admired my completed woodworking projects and cabinets and handmade gunstocks, but few have had the patience required to actually attempt it. Of course, being all handwork, and taking quite a bit of time to accomplish, it is not suited to most commercial situations.

As for hobby woodworkers, there seem to be two schools of thought. The first hasn’t the patience to deal with any finish that can’t be applied with either a spraygun or power roller. Most of the woodworking publications energetically promote equipment-intensive commercial production methods even to the amateur, and feverishly foster this attitude. At the the risk of sounding cynical, I ask you Gentle Reader, is owning an airless spray system really necessary to perform quality woodworking, or is such equipment more of a profit center for manufacturers and retailers?

With this statement, I am certain I would receive complaints from advertisers to this blog (if I had any), and perhaps even threats about pulling said advertisements. Good thing I don’t give a rodent’s ruddy fundament about such things or the feeling of rejection might crush my fragile ego like a raw egg in a little boy’s back pocket (シ)。

At the other extreme, there are devotees of the Neanderthal school that have been indoctrinated by romantic viewpoints in the woodworking press, or influenced by things written in books a hundred years ago. These gentle souls are drawn to archaic finishes such as boiled linseed oil, beeswax, and unicorn piss.

To the production-method advocates I say save production methods for production work, and seek better quality for your handmade projects. To the Birkinstock-wearing Neanderthals I say, there is a reason old unrestored furniture and gunstocks are dark, grungy, and yes, dirty: Linseed oil and beeswax. Consider what you want your work to look like in 100 years. Certainly not cracked, water-damaged, and dirty. And genuine unicorn tinkle is practically impossible to come by nowadays, even on Amazon.

I promise you the results will be worthy, with no downside, and your planes, tools handles and wooden projects will not only look better longer, but will be tougher and more stable.

The Abura Dai

I would like to add a note here about a Japanese technique intended to improve the stability of handplane bodies, namely the “Abura Dai 油台” which translates to “Oil Body.”

The idea is to soak the oak body (dai) of a handplane in low-viscosity spindle oil until it takes up a significant amount thereby minimizing moisture exchange and improving the stability of the handplane’s body. Does it work?

I own and use a 65mm abura dai handplane I purchased as a sample around 6 years ago, and which seems to be fairly stable. But I am not a fan of abura dai for two reasons. First, by design spindle oil never dries and is always wet. Therefore, the dai is always a little oily and definitely stinky. I don’t like the smell of spindle oil nor do I want to feel it on my hands unless I’m being paid for it.

Second, it makes the sole of the handplane softer, an area I would prefer remain harder, increasing wear noticeably. I was told about the failings of the abura dai by professional woodworkers many years ago, and the wear on the sole of my 65mm plane confirms their observations.

I encourage Gentle Reader to give the London Finish a try. You will like the results. And please share your impressions with me and other Gentle Readers.

Until then, I have the honor to remain,

YMHOS

Byodoin Temple on a clear Winter’s day

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 by using the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may my all my planes warp into pretzels.

In The Blood

Make of yourself an honest man, and there will be one less rascal in the world.

Thomas Carlyle 1803 – 1855

It behooves a man to know human nature in general and his own nature in particular, at least in your humble servant’s opinion, which, along with $1.25, will buy you a soft drink in a can.

Has Gentle Reader ever wondered why people do some of the things they do? While it makes perfect sense to work diligently for the necessities of life such as food, clothing, and housing, we do many unnecessary things that yield no apparent profit, for example gardening, despite fruits, vegetables and even flowers being easier and cheaper to purchase in a grocery store. And how about the large, lush green lawns and ornamental plants and trees we install around around our homes and maintain at great effort and expense, plants that serve no practical purpose but cost us time and money and other resources?

What whips drives us to these excesses?

I daresay this isn’t just a guy thing, either. Many ladies insist on weaving, knitting, and sewing clothing and home furnishings by hand even when mass-produced, inexpensive products of similar quality and utility can be readily purchased from stores anywhere. It just doesn’t make sense, and I say that as a husband that, at the behest of She Who Must be Obeyed, has spent thousands of dollars on CNC sewing machines with unobtanium armatures and smoothie attachments all to make quilts that never spend a second on a bed and seldom even see the light of day.

What is this madness that has her gripped in its talons?

But I fear the madness runs deeper still, for many males of the species spend inordinate amounts of time and money buying trucks, ATVs, clothing that makes them look like trees, camping gear and weapons of death and destruction (aka WODADs) in preparation for hunting season, a time when otherwise sane people don orange costumes and chase Bambi around the mountains and forests just to obtain the most expensive meat to be found anywhere in the world. It’s just nuts.

And don’t even get me started about fishing. A good time was had by all during these hunting and fishing expeditions, but the benefits are impossible to calculate. It just isn’t logical…

Woodworking is useful for making housing and furniture and many of the tools essential to civilization, but what about woodworking as a hobby? Isn’t it quicker, easier, less expensive and more sliver-free to buy pre-fabricated houses assembled on-site with bolts and furniture made of MDF, plastic and steel excreted by Chinese factories? Of course it is, so what is this friking parasite madly manipulating levers in our brains compelling us to make these things with our own hands instead?!

I don’t know why we do these things, I only know we want to do them and that doing them gives us satisfaction. But I do have a humble theory I will present for Gentle Reader’s consideration, just for giggles.

I believe that the habits and actions that successfully preserved our ancestors long enough for them to produce and raise each generation of humans became imprinted in each subsequent generation’s DNA.

Successful farmers survived since ancient times leaving descendants with their genes. I suspect it is the farmer gene that compels so many of us to grow fruits and vegetable and surround our homes and cities with lawns and plants, a form of agriculture similar to that which kept our ancestors from starvation. It’s the only possible explanation for the universal compulsion to plant stuff.

The children of women who spun, wove, knitted and sewed clothing and bedding survived cold winters inheriting the sewing gene. I’m not sure where smoothie attachments fit into the equation, but sewing machines are clearly part of the compulsion.

The children of successful hunters and fishermen survived too. The compulsion to perform these activities is still strong in many, your humble servant included. I’m sure you’ll agree that the ritual of talking around the evening camp fire about the big one that got away while saber tooth tigers and cave bears prowled in the shadows beyond the fire is much much older than recorded history.

Somewhere not far out on a limb of Gentle Reader’s family tree are hundreds, perhaps thousands of ancestors that shaped lumber to make houses to protect and keep their families warm, and beds, tables, benches and chests to make life cleaner and more pleasant. This is a healthy and noble urge, one that, like farming, sewing, hunting and fishing has been useful in keeping body and soul in intimate contact for many thousands of generations in humanity’s past.

My father inherited the woodworking gene from a carpenter ancestor, one of two brothers that left England in the 1600’s to travel to South Carolina by leaky boat. It appears I in turn have passed it down to my sons and grandsons. I am glad of this for mayhap I hear the toenails of wolves clicking on stones in the dark shadows just outside the firelight just now, so a solid door of thick hewn oak with a sturdy cross-bar may come in handy before the morning.

But for now, please ignore the snuffling and scratching noises at the door, pull up a chair by the fire and let’s get started on that chess game, shall we?

YMHOS

Waiting for dark, and dinner

If you have questions or would like to learn more about our tools, please click the see 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 by using the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may my riding lawnmower lose power as I pass between two ready-mix concrete trucks on the Tomei Highway.

The Care and Feeding of the Wild Mortise Chisel – Part 2

By concentrating on precision, one arrives at technique, but by concentrating on technique one does not arrive at precision.

Bruno Walter

As mentioned in the previous post in this series, in Japan the mortise chisel is called the “Joiner’s Chisel,” because it is specifically designed for precisely and quickly cutting the many small mortises craftsmen in the joiners trade use in making doors, windows, shoji, screens, furniture and cabinetry.

Why must it cut mortises quickly? Simply because a few seconds of time wasted on each one of many mortises cut during the workday by an uncooperative chisel will quickly add up to hours of lost productivity.

Why must it cut mortises precisely? Simply because defects hidden inside mortises with poor internal tolerances tend to accumulate and too often turn what would otherwise be a well-made piece of furniture or joinery into a rickety old Chinese lawnchair.

In this post we will discuss what to look for in a mortise chisel, and how to correct some typical problems. Most of the concepts discussed in this post are applicable to oiirenomi and atsunomi used for cutting mortises as well, although such chisels lack the same shape advantages.

Klipstein’s Law of Thermodynamics

Just in case Gentle Reader didn’t notice, your humble servant has strong opinions about mortise chisels, partly because I was trained by no-nonsense professionals to cut hundreds of mortises in a single sitting, and partly because bitter experience has taught me the truth that sloppy mortises result in both sloppy products and crushing headaches. Nothing like a bunch of tiny errors when making a series of latticework doors to painfully confirm the validity of Klipstein’s Law of Thermodynamics: “Tolerances inevitably accumulate unidirectionally toward maximum difficulty to assemble.”

Because of this hard-earned experience we have given our blacksmiths specific dimensional tolerance criteria for the mortise chisels they make for us. I can’t always clearly hear what they are muttering in response to my pointed insistence, but it sounds something like “frikin prissy pink princess expects too much of a damned chisel.” Your most humble and obedient servant, however, is much too dignified and polite to respond in so many words, but at such times I think they are stubborn old farts that have never used a mortise chisel. In any case, those who use our mortise chisels benefit from the princess impulse in us.

What to Look For

Mortise chisels are used routinely by only the most skilled craftsmen. Despite their simple appearance, mortise chisels are required to cut to tighter tolerances than other type of chisel, but because they are handmade in the traditional manner without the use of CNC machinery, and because perfection is unattainable in mortal endeavors, they are seldom perfect when new, so Beloved Customer should plan on tuning your mortise chisels before doing serious high-volume work. Indeed, it has long been standard practice among Japanese joiners to modify their chisels and planes to their preferences, and correcting the dimensional imperfections of mortise chisels is at the top of the list, not because they tend to have more imperfections than other chisels, but because more precise work is expected of them.

If you recall some of the mortises you have cut before now you may have noticed that despite your best efforts and forehead-splitting concentration, the sides ended up out-of-square with the workpiece’s top surface, or the side walls were raggedly gouged, or even undercut. These defects are not unusual, and may be due to pernicious pixies, your technique, or perhaps a combination of both, but my money’s on the chisel being the culprit.

Please examine your mortise chisel. If it does not meet the ideal standards in the list below (and it won’t), you should make corrections. You’ll be glad you did. There is a link to a document below that illustrates the ideal mortise chisel as well as some typical problems that may prove useful.

  1. The plane formed by the flat lands surrounding the hollow-ground ura depression should be truly flat and without twist over its entire length from cutting edge to shoulder.
  2. The blade’s width should be consistent over its entire length. Alternately, it is acceptable if the blade’s width becomes just slightly and gradually narrower moving from cutting edge to neck. But not too much. On the other hand, a blade that widens towards the neck is an abomination to be avoided like the spotty-bottom footpads at the California Franchise Tax Board.
  3. The blade’s sides should be flat, planar, free of twist, square to the ura, and square to the blade’s top face. Accordingly, a cross-section taken anywhere across the width of the blade should be rectangular anywhere along its length, with all corners 90°. Picky details, but they can make a big difference in the quality of the finished mortise.
  4. The top face (surface where the brand is stamped) need not be straight, but it must be square to the sides at all points along the blade’s length.

Make no mistake, this is a tall order in a hand-forged tool that has never seen a milling machine, planer, or CNC grinder. Few handmade mortise chisels can meet these standards when new, but these details can make all the difference.

Let’s begin the examination part of this job. You will need a 6~12″ straightedge, a small precision square like the Matsui Precision products we carry, and a vernier caliper.

Record Your Observations

Too often the number of dimensional irregularities that require attention are complicated enough to create confusion. This can result in even experienced people making one irregularity worse, or even generating new problems, while attempting to resolve the initial irregularity, like inadvertently creating more knots while trying to untangle a snarled mess of string.

To avoid confusion, I recommend  you make a simple orthogonal hand sketch of your chisel to record irregularities. This sketch should show at least four views of the blade including left and right sides, its face (opposite the hollow-ground ura), and an end view looking towards the cutting edge’s bevel. You may also need to make a few cross-section sketches

Record the results of your examination as annotations and red lines on these sketches to help you plan and execute the work of correcting any problems you may find. There are always a few, and you will need to keep track of each one, and its relationship with the others.

Examine and True the Ura

The first step is to check the ura, the polished lands (flat surfaces) surrounding the hollow-ground depression on the chisel’s back. These must be flat and in the same plane (coplanar). This detail is very important.

A straightedge is good enough for a quick examination, but a more reliable method is to use a granite surface plate. A less expensive and handier option is a simple piece of ⅜” or thicker float glass. 

To use a glass surface plate, apply marking pen ink or Dykem to the ura’s lands. Smear a tiny amount of finishing stone mud around on the glass plate. With the entire blade resting on the plate, and finger pressure straight down in the middle of the blade’s face, move it in a oval pattern through the sharpening stone mud. The ink or Dykem at the high spots will be rubbed off, but will remain at the low spots. This will show you where and how much material must be removed to flatten the ura’s lands

Then, true the ura using a diamond plate, diamond stone, sharpening stones, and/or the glass surface plate. This step is not so important in the case of other types of chisels, but a mortise chisel must have a reasonably flat ura. Without a planar ura, the rest of your examination may be inaccurate. The article at this LINK contains a more detailed discussion with pretty pictures.

Do this work carefully. If you heavy-handedly remove too much steel, the useful life of the chisel may be dramatically reduced. This is a one-time operation in the life of most chisels.

Examine the Blade’s Width and Taper

Next, check the width of your mortise chisel measured across the ura using a vernier caliper or micrometer or other reliable gauge. Relative width is what you need to check, not absolute inches or millimeters, unless you expect your chisel to cut precisely-dimensioned mortises, something that is seldom necessary in the real world.

Measure the blade’s width at five or six locations along the cutting edge, in the middle, and near the neck before it narrows. Make a sketch of the blade and annotate these dimensions on it

Use the glass surface plate at this time to check the sides for flatness. The black oxide surface skin will be worn away by the sharpening stone mud marking the high points, but don’t let the change in cosmetic appearance bother you.

Ideally, the blade will be the same width its full length. However, it is usually acceptable if the blade is slightly wider at the cutting edge than near the shoulder. But if it is wider at the shoulder than the cutting end, it will bind in the cut, tend to split the mortise, and the finished mortise will be skiwampus. This must be remedied by grinding the blade on diamond plates and polishing on sharpening stones.

But don’t do anything yet since there are more details you need to examine first. Just make a note on your little sketch.

Examine the Blade’s Sides

Straight Sides

Use a good straight-edge to check both sides of the blade’s sides. They must be straight. If they curve in or out it will be difficult to convince it to cut a clean straight mortise. If the blade is banana-shaped, it can’t cut a straight mortise anymore than a politician can tell the truth while his heart beats (it’s rumored that some have hearts).

If the blade’s sides are not straight, they must be corrected by carefully grinding and polishing them. But hold your horses there Hoss, don’t do anything drastic yet, just make a note on your little drawing: there’s still more to check first.

Flat Sides

Next check the sides of the blade across their width. They must be either flat (best) or hollow ground (acceptable). If they bulge outwards the blade will bind and can never cut a clean precise mortise, so corrections are absolutely necessary. 

Mark any irregularities on your sketch.

Right Angled Sides

The sides of the blade should be at right angles (90°) to the ura lands. If not, the chisel will skew left or right during each cut, a common problem with most chisels. Gentle Reader has no doubt experienced this.

Slightly less than 90˚ may be acceptable (but less than ideal) if both sides are the same angle. If, however, one side is 90˚, for instance, and the opposite side measures 80˚, well that is not good and may require correction.

For now, just mark any irregularities on your sketch.

Examine the Blade’s Face

Next, examine the chisel’s face (the surface with the brand). 

This surface need not be straight along its length. It doesn’t even need to be flat across its width, but can even be be hollow or bulging to a minor degree without causing trouble. But you do need to pay attention to two key details. 

First, if it is hollow or bulging, the curvature of the bulge or hollow across the blade’s width must be uniform. If not, you should grind it flat. 

The second thing to check for is that a line between and touching the corners where the surface of the face meets the blade’s sides must be parallel with the ura. In other words, if you draw a line 90˚ across the width of the face, that line should be parallel with the ura. If it isn’t corrections are necessary.

Why does the relationship of these two surfaces with each other matter? Two reasons. First, if they are not properly aligned, and assuming the ura is flat, it means the blade is thicker in cross-section at either the right side or left side. There is a strong tendency for the bevel and to become skewed during sharpening, with the result that the cutting edge is not square to the center line of the blade’s long axis.

Of course a skewed cutting edge will push the blade to the right or left in the cut, and cannot cut a flat bottom, a serious defect in advanced mortise and tenon work. This deformity can be compensated for with careful attention during sharpening, but you should not have to work so hard. Better to correct the problem now and get it over with once and for all, I promise.

The second and most important reason is that the skewed bevel will cause the blade to dive to the right or left when cutting a mortise ruining precision and gouging the mortise’s walls. This is different from the problem noted in the previous paragraph, although it may seem to be the same. It’s a serious defect in a mortise chisel, one that causes the most self-doubt among craftsmen.

Even the very best blacksmiths frequently fail to give this surface proper attention You are hereby warned: Do not underestimate the importance your chisel’s face.

Examine the Blade’s Corners

Finally, examine the two lines formed by the 90° intersection of the sides and the ura. Are they clean and sharp, or are they ragged, radiused or chamfered? These corner edges serve an important function in dimensioning and shaving the mortise’s side walls. They must be clean and almost acute enough to cut your fingers, but please don’t.

If they are not right, you can correct this now or a little bit at a time during subsequent sharpening sessions. The important thing is to be aware of any defects so you can make corrections, so make a note on your little sketch.

The Plan

You should now have a sketch describing those areas that need to be corrected. Use it to make a plan. A rough sketch showing how a mortise should should be and common problems is linked to below.

Beloved Customer should keep two important factors in mind in mind when planning and executing corrections to mortise chisels.

First, you should strive to achieve the corrections with the minimum expenditure of time, effort and stone/diamond plate, and while wasting the minimum amount of steel. I am not saying work hard or work fast, but rather to work efficiently.

Second, you should work carefully to avoid creating new problems while attempting to fix existing ones. This is why you need a plan, one that will vary a little with each chisel, to guide you in working efficiently and carefully. Remember, double work takes more than twice the effort, and often wastes lots of expensive steel.

I suggest you write your plan down.

I also recommend you keep the following points in-mind when considering your plan and its execution.

  1. As mentioned above, the first step is to true the ura so it is planar. It need not be perfect at first; Close is good.
  2. After the ura is more-or less planar, grind the right and left side, whichever is in better shape, straight along its length, flat (or sightly hollow) across its width, and perpendicular to the planar ura using diamond plates. Electrical grinders and sanders can be used, but there is a real risk of ruining the temper if you allow the steel to get hotter than is comfortable to touch, so great caution is necessary. This means working slow and using lots of water.
  3. When one side is done, grind the opposite side straight along its length, flat (or sightly hollow) across its width, and perpendicular to the planar ura using diamond plates (if necessary). It will be at the same angle with the respect to the ura as the opposite side, of course. Here is where more caution is necessary: pay close attention when grinding this side to make it parallel with the opposite side. Worst case, the blade width measured across the ura can be slightly wider at the cutting edge than the neck, but uniform width is best. On the other hand, a blade narrower at the cutting edge than near the shoulders is useless for cutting mortises and must be corrected.
  4. Finally, grind the face of the blade (the upper surface with the brand) so that any point along its length is parallel with the ura. It need not be straight or even perfectly flat over its entire length, just parallel with the ura to guide the chisel straight in the cut.

At the conclusion of the steps described in this article, your mortise chisel should now have an ura with all the lands surrounding the hollow-ground swamp forming a single flat plane. You should also have a nice little sketch describing all your chisel’s imperfections and a plan for making corrections.

In the next article in our joyous journey ass over teakettle down this rabbit hole of obscure woodworking tools, I will describe my observations about a particular mortise chisel, the plan for adjusting that chisel, and show the execution of that plan. Indeed, I have a box of chisels that are simply wiggling and squeeking with frantic anticipation to be first!

YMHOS

P.S.: After many months, we now have mortise chisels in-stock again. They won’t last long. Prices and availability can be checked at this LINK

A formal procession of frogs mocking the feudal lords of medieval Japan. I bet you haven’t seen many frogs walking around with swords. Such work was a rare opportunity for artists and the common people to mock the rich and powerful nobles that ruled the many little nations of the Japanese islands at the time with a steel and despotic fist.

If you have questions or would like to learn more about our tools, please click the see 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 thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may my mortise chisels all turn to glass.


Other Articles in “The Care and Feeding of the Wild Mortise Chisel” Series

Japanese Handsaws: The Twins

Communism is the opiate of intellectuals [with] no cure except as a guillotine might be called a cure for dandruff.

Clare Boothe Luce

his article is a show-and-tell about a matched set of custom-forged handsaws which have been your most humble and obedient servant’s trustworthy companions in the noble profession of making sawdust for many years.

The Twins

The archaeological record suggests that, at least in areas of the world where rusty remains have been excavated, the standard metal handsaw in ancient times had rip teeth only. As evidenced by the superior mental powers Gentle Reader exhibits, Woodworkers have historically been extremely intelligent people, so no doubt many sawyers, carpenters and joiners back in the mists of time independently discovered that filing (or stoning) their sawteeth to an acute bevel angle and alternating the direction of the bevel made the saw cut much faster and with less effort across the grain (i.e. crosscutting).

With this discovery, the crosscut saw was born, and thenceforth has been a worthy servant to its masters and a good companion to its elder sister the rip saw.

In modern times with the proliferation of inexpensive (and dangerous) circular saws, rip handsaws have become as rare as selfless tax collectors, but the combination of a rip saw for making cuts parallel with the direction of the grain of the wood, and a crosscut saw for making cuts perpendicular to the grain of the wood has been common-sense among those who value accuracy and efficiency at least since the proliferation of carbon steel saws.

Some decades ago while working as a carpenter, your humble servant realized he needed a set of larger rip and crosscut saws for fabricating joints in timbers. The search resulted in the purchase of several saws, but the set described in this article are the two I have come to rely upon for such tasks most.

Both saws were hand-forged 70~80 years ago in Sanjo, Japan by a saw blacksmith named Azuma with the brand-name of Nakaya Choujiro (中屋長次郎), a venerable name in Eastern Japan. The grandson of this blacksmith is still producing saws in Sanjo today, including the Seijiro brand ryouba saws we carry. Nowadays nearly all of his production has shifted to short saws used by luthiers.

I found these saws in a tool store in Tokyo which is now defunct due to the owner’s inconvenient relocation to the big lumberyard in the sky. At the time of purchase, the store owner informed me they were originally commissioned by, and custom forged for, a Miyadaiku (temple carpenter) in Arakawa Ward of Tokyo, but sadly he had moved on to sorting boards in heaven without picking up these sawblades, leaving them sad and lonely in a cabinet hidden behind buckets of paint and roofing materials.

I get misty remembering their joy at being rescued after languishing so many years in darkness…

The Bukkiri Gagari Rip Saw

The saw in the photograph above and at the top of this article is a large kataba (single-blade) rip saw with aggressive, progressive-configured teeth called a “bukkiri gagari.”

“Bukkiri gagari” is a name used for large rip saws with this style of handle. The word “gagari“ refers to a large rip saw. The word “ bukkiri” probably means “chopped” or “cut down,” referring to the shortened tang.

The pointed tang, typical of handsaws intended to be fitted with a straight in-line handle, was bobbed at the time the saw was forged, evidence that it is not a conversion, but was intended to be a bukkiri gagari when just a twinkle in Grandfather Choujiro’s eye.

The large brownish-orange discoloration seen on the blade is neither corrosion nor a shadow due to poor lighting, but a remnant of the heat-treating process common to saws forged in Eastern Japan, more evidence of quality handwork.

The blade’s length measured from tip to the beginning of the tang is 425mm (16-5/8″). The cutting edge (teeth) measures 330mm (13″), making it a 1-shaku 1-sun blade a slightly unusual length. The blade’s overall length measured from the tip of the exposed tang to the tip of the blade is 625mm (24-5/8″). It measures 130mm (5-1/8″) at the widest point at the tip of the blade. The back of the blade has a slight curvature away from the cutting edge as is standard for larger rip saws forged in Eastern Japan.

A closeup of the tang of the bukkiri gagari member of the team. Sorry for the poor focus, but the hand-carved signature of Nakaya Choujirou (中屋長次郎) is plain to see. Some people prefer to jamb the handle on permanently, while I prefer the options a wedged handle provides. The wedge can be inserted from front or back, top or bottom, changing the angle of the handle and its distance from the cutting edge. The forge-welded connection between iron tang and steel handle is more visible in this photo. This detail is coveted by aficionados of Japanese saws as witness of quality handwork.

I made the handle from Japanese White Oak stained mahogany color. It measures L270mm x w38mm x t30 (10-5/8″ x 1-1/2″ x 1-3/16″).

No doubt Gentle Reader is familiar with the more common Japanese handsaws with straight, softwood handles. This style of handle is called a “shumoku tsuka” 撞木柄 (shoe/moh/ku/tsu/kah) and is attached to the blade’s tang at an angle.

A shumoku is a wooden mallet used to strike bells in the Buddhist religion. I don’t know why this word is used for a saw handle; No one I have asked has been able to provide useful insight.

The shumoku handle can be attached to most any Japanese sawblade with a straight tang. It has several advantages. First, compared to the standard long handle attached in-line with the tang, it makes the saw much shorter in length and therefore handier for working in tight spots. This is especially useful when making vertical cuts from below for joints in the ends of large timbers resting on sawhorses or during erection where a long handle would get in the way.

The second advantage of the shumoku handle is the fact that, when combined with the stiffer blades of large rip saws, the user is better able to bring the stronger muscles of legs, back and both shoulders into play for more powerful cuts, an ergonomic principle similar to the thumbhole handle once common in Western handsaws.

The stance this handle makes possible also provides more leverage (greater moment couple) when cutting in tight situations and at unusual angles than a longer, straight handle can. This last factor makes the bukkiri gagari saw most valuable IMHO.

The Crosscut Saw

Notice the curvature to the back which is the approximate inverse of the curvature of its twin the bukkiri gagari saw shown above. Subtly beautiful.

The crosscut member of this dynamic duo is also a kataba 片刃(single-edge) saw with a custom-made but more ordinary straight handle.

It’s overall length is 845mm (33-1/4″), with 420mm (16-9/16″) of that being the blade extending past the handle. The blade is 125mm (4-15/16″) wide at the tip.

The cutting edge portion of the blade matches its companion at 330mm (13″), so it too is a “Juissun” saw, meaning 11 sun.

It too has a beautiful curvature to its back which in this case is directed towards the cutting edge instead, giving it a diligent posture. As is the case with all matched sets forged by the same blacksmith (at least in Eastern Japan) the curvature of the back of each saw is the inverse of its partner so that they nest neatly against each other all lovey dovey. Although these cosmetic details have little if any practical purpose, Japanese shokunin are unreasonably fond of these matched saws, as am I.

Of course, the handle is approximately the same length as the the blade (not including the tang), and oval in cross section measuring 30 x 35mm x 425mm (1-3/16″ X 1-3/16″ X 16-3/4″). We will discuss how to make this type of handle in a future article.

I made this handle long ago from a piece of scrap Akita Sugi cedar (cryptomeria) , wrapped it tightly with copper wire at the mouth end to reinforce against splitting, applied a dab of solder to lock the wire in-place, and finished it by rubbing the wood with a tool called an “uzukuri” made from skinny but hard plant roots to partially remove the softer summer wood leaving an excellent, textured surface that won’t slip no mater how wet with sweat it becomes. I love Akita Sugi

Gentler Reader (may the hair on your toes ever grow long!) may be wondering why one would use a short, sideways handle for a rip saw but a long straight handle for a crosscut saw. An excellent question indeed and further evidence of your superior intelligence!

Some crosscuts in timber work benefit from a longer reach. But more importantly, while the longer handle provides less power than the shumoku handle, it provides more control, essential for precise crosscuts. The way it was explained to me is that the large bukkiri gagari rip saw is used up close to the face and “guided by the nose,” while the large crosscut saw is guided from further away by the eye. Give it a try and you’ll see what I mean.

Although I haven’t used these saws professionally for far too long, I had the teeth sharpened and plate tuned a few years ago by a famous blacksmith and saw sharpener named Nakaya Takijiro located in Kawagoe.

In one or two of the photos you may detect the little marks his tapping tapping tapping hammer left on the blade when he trued and corrected it. No, he didn’t straighten it, but he induced internal stresses to relieve some oil canning that had existed from Choujiro’s forge. He also made other subtle stress adjustments with his little hammer that made the saw track straighter and smoother with less friction as it heats up. What a difference it made! He is literally a genius with a sawblade.

The blacksmith’s hand-cut signature on the crosscut saw: “Nakaya Choujiro.” The blade was shaped and tapered in thickness by hand using a “sen” scraper, as evidenced by the visible marks. Close observation reveals that the soft tang is not electronically welded to the blade as has become SOP post-WWII, but is forged welded, a technique lovers of hand-forged saw greatly appreciate. Sadly, most of the surface corrosion occurred before your humble servant rescued these excellent saws.

I don’t use these saws much anymore, but I enjoy taking them out of their protective wrappings once or twice a year to clean and oil them, catch up on news, and sing a song of sawdust together. They love to sing.

I hope you found this little show-and-tell amusing. I have other unusual saws I will introduce in future.

Until then, I have the honor to remain,

YMHOS

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Please share your insights and comments with everyone by using the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may the teeth on my saws all snap off.

The Japanese Sumitsubo Inkpot 墨壺: Part 3: The Modern Sumitsubo

The newest Cylon-inspired modern sumitsubo by Shinwa

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 Mushashi – Go Rin no Sho

In the previous article in our series about the Sumitsubo, we examined some traditional wooden examples, and a plastic version of the same.

In this edition we will take a look at the modern version sold in hardware stores around Japan.

In the previous article your humble servant mentioned that this style of sumitsubo appears to have been designed by Cylons, the chrome-plated red-eyed nemesis of the Battlestar Galactica and her brave crew. Gentle Readers must decided for themselves whether or not alien machine lifeforms from a far galaxy were engaged in the design process or not, but I have no doubts on the matter (シ).

The Design Concept

These modern sumitsubo function much the same as traditional wooden sumitsubo in that a line, stored on a reel, is spooled out through a reservoir containing absorbent material soaked with ink, becoming partially saturated with ink. The wet line is then secured to the material to be marked at one end using a “karuko” bob with a needle. At the opposite end of the material, the line is aligned with another mark, tensioned, lifted up and released snapping against the material and leaving behind a line of ink.

Besides the intergalactic alien design influence, the most obvious difference between these modern sumitsubo and the traditional ones is that the line, the reel, and the ink reservoir are entirely enclosed in a cleverly-designed, tough and lightweight plastic housing which not only keeps the ink from drying as quickly, but permits the tool to be dropped into a tool bag or toolbox without risk of getting black ink all over everything. Much more convenient.

The ink reservoir is concealed under a little plastic hinged door that one opens to add ink to little sponges. In the better sumitsubo this reservoir has rubber seals and special slits to prevent ink from leaking. This combination of sponges and seals works quite well so long as one doesn’t add too much ink. But everyone does this at least once…

In the case of automatic sumitsubo, as are the examples shown, a coil spring enclosed in the reel mechanism automatically spools the line back onto the reel in preparation for the next snap. Some versions lack this spring and must be rewound by rotating the reel using one’s fingertips.

Please note that this spring action, while quick and convenient, is not 100% blue bunnies and fairy farts because the karuko’s sharp little point can give the user a serious boo boo if control is lost. To prevent embarrassing injuries (i.e. leaky eyeball syndrome), the karuko sold with most of these sumitsubo are designed to automatically retract the needle safely into a plastic housing when released.

As someone who has unintentionally initiated one or two haphazard tattoo patterns on hand and arm over the years with flying karuko needles, your humble servant highly recommends Gentle Readers “stick” with these retractable needles. And don’t forget your safety glasses.

Changing the line of the modern sumitsubo is much easier than with traditional sumitsubo because there are no holes to thread the line through. All that’s necessary to change a line is to open the ink reservoir, remove the reel, tie the new line to the reel and karuko, replace the reel, lay the line through the reservoir, and close the lid. Eazy peazy japaneazy.

Gentle Reader may recall from the previous article that, when using the traditional sumitsubo, one must simultaneously press down on both the line and wadding in the ink well with a bamboo sumisashi as the line is spooled out to ensure an adequate amount of ink soaks into the line. This is not possible in the modern sumitsubo with its covered ink reservoir, so instead, one pushes down on a rubber button while spooling out the line to achieve the same results. This rubber button in turn presses down on the line and sponges transferring ink to the line.

Major Brands of Modern Sumitsubo Available Today

There are two major brands of sumitsubo on the market in Japan today: Shinwa of steel square fame and Tajima best known for its tape measures.

Two of both brand’s most popular models, in various states of undress, are shown below.

When it comes to sumitsubo, Shinwa is the older and more experienced of the two, but Tajima has more eye-catching products and a powerful marketing department with a nation-wide distribution network.

A side view of the Shinwa Sharp-line sumitsubo with extra-fine line. The design looks much like a space ship with a non-slip grip. Phasers and proton torpedoes are currently not available options for this model. Maybe next year.
The Shinwa Sumitsubo with its lid open. Yellow sponges to contain ink are mounted in the lid and body. A blue rubber seal installed in the lid seals the ink reservoir to prevent leakage and reduce evaporation. Although not visible in this photo (see the photo at the top of this article) the sponges and line can be squeezed together by pressing on a rectangular rubber button in the lid. The stainless steel pin visible to the left of the reservoir guides the line and keeps it from abrading the plastic. A stainless steel ring at the sumitsubo’s mouth (far right) guides the line and keeps it from abrading the body too. The needle in the karuko is spring-loaded so if left on its own it retracts into the karuko’s plastic body, but in this photo it is held extended with tape. The karuko has a rubber “O” ring of sorts molded to its end that fits tightly into the body’s mouth to prevent leakage. The Tajima Sumitsubo lacks this detail. At the far right end of the lid a black operable metal tab can be seen extending from the body. This helpful widget is used to precisely locate and press down on the line before the snap. This too is not found in the Tajima version. At the far left can be seen a loop for attaching the tool to the toolbelt or safety harness with a lanyard as required by Japan’s safety regulations when performing overhead work. Beam me up, Scotty.
The newest Shinwa sumitsubo disassembled, a three second operation accomplished without tools. The body with the lid to the ink reservoir and its sponges and rubber seals is open in the center. The reel is upper left. The circular casing that secures the reel within the body and contains the brake and drag, features also not available from Tajima, is lower left. The karuko with its spring-retracted needle extended with tape is located center right. Liquid ink is dripped onto the sponges and the lid is closed locking the reel and line in-place. A coil spring inside the reel assembly spools line back onto the reel automatically.
The Tajima version of the modern sumitsubo. It has a slightly more organic shape reminiscent of a gourd, a traditional motif in Japan. The narrow waist in both the Tajima and Shinwa models ensures a comfortable one-handed grip in the field. This sumitsubo has a round rubber button located to the right of the word “EVO” to actuate pressure on sponges and line.
A side-view of the Tajima sumitsubo showing the lid’s hinges. The karuko is inserted into the mouth in this photo, and is larger than the Shinwa’s karuko.
The disassembled Tajima Sumitsubo. It has two blue sponges mounted inside the body, instead of Shinwa’s yellow sponges, one of which is mounted in the lid. Accordingly, the underside of the more complicated circular rubber pressure mechanism can be seen in the open lid. A black rubber seal mounted in the lid keeps ink from leaking from the reservoir (at least that’s the idea). Unlike the Shinwa, the line must be thread through the mouth without the karuko attached, a little less convenient. This sumitsubo has two stainless steel pins guiding the line to and from the reel, although I’m not sure why two are necessary. It too has a stainless steel ring at the mouth to limit wear, but it can’t be seen from this angle. In addition, a hard, wear-resistant plastic block is inserted where the line exits the reservoir to the right to reduce wear. The reel is held in place by the plastic ring bottom left, which is twisted then locked into place when the reservoir’s lid is closed. This tool comes in various sizes and colors and is probably the most popular sumitsubo commercially available in Japan today.

Your humble servant, being gleefully addicted to trying out new tools, owns both brands of sumitsubo. Perhaps I need a 12-step program and a good detox to mitigate my tool-based delirium tremens? In any case, I’m convinced Shinwa products are perhaps a little superior in performance, but the Tajima sumitsubo are undeniably good too.

As I wandered around a construction project in Chiba Prefecture I’m in charge of last week I paid attention to the sumitsubo workers were using and observed that Tajima products were in greater evidence. Not a scientific study by any means, but more accurate than the flyblown tripe the hopelessly corrupt World Health Organization calls science lately.

A few weeks ago I visited a local hardware store I do business with regularly. Although it’s not the first or even the second building that has housed this business at this same location in Suginami Ward in Tokyo, the family that owns it has been selling tools and building hardware to contractors and professional craftsmen for over 100 years. Inside it has tools and building supplies literally stacked to the ceiling, much of which is cantilevered precipitously over the narrow, crowded aisles between steel shelves to the point where entering the store and moving around is not a simple task. A death trap should an earthquake strike, I fear.

The current owner is 90+YO with a warm smile and honest habits who is easy to trust. I asked him which sumitsubo products are most popular among his professional customers. His answer was that they seem to buy the Tajima products more, although he couldn’t give a single reason why. I suspect the fact his shelves are full of Tajima products with nary a Shinwa product in-sight has something to do with their selections.

Tajima’s distribution network is hard to beat.

My old ten-year old Shinwa sumitsubo. It’s currently setup for construction jobsite use with heavier line and a karuko with both a needle and super-magnet base for use with structural steel and LGS studs. The reservoir lid’s hinge is half broken, but still works good enough. I purchased the Cylon blue Shinwa sumitsubo dissected above as a replacement in anticipation of its imminent retirement.

Inklines

The lines used in sumitsubo were once all made from either hemp or silk fibers, I’m told. Nowadays, hemp can’t be had for love or money, but silk is still available. Modern fibers made from polyester and nylon are most prevalent of late. Better lines contain kevlar or spectra fibers for extra strength.

I am fond of thin (>0.4mm) lines for cabinetwork because they make cleaner marks, but skinnier lines are less durable and the marks they leave are less visible from a distance and on rough surfaces, so for construction projects, although 1.0~1.5mm lines can be purchased, 0.6~0.8mm lines are what most people use.

Conclusions

I am fond of the simple, elegant, antique appearance of the ichimonji-style wooden sumitsubo.

A carpenter-made ichimonji-style sumitsubo in the workshop. We share the same ebony karuko

I have used the more modern Genji-style wooden sumitsubo for many years, and like them enough to have one mounted inside my toolchest for good luck. Like many older craftsmen, I appreciate the appearance of a tool beautifully hand-carved from attractively figured colorful wood, and think the traditional wooden sumitsubo feels better in the hand and adds dignity to the work.

But the modern Cylon-designed plastic sumitsubo is cheaper, tougher, and much more convenient, which is why I reach for one when I need to snap a line. Who was it that sang: “The times they are a-changin?”

Which style do you prefer?

YMHOS

To pixies that stray too near, the little turtle gives his best Lee Van Cleef glare and growls: “Stay away, vile creatures, or I’ll bite you in two, snicker-snak!” He is most persuasive.

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 all Gentle Readers using the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, thuggish Twitter, nor a US Senator’s Chinese girlfriend and so won’t sell, share, or profitably “misplace” your information. May my karuko ravage my family jewels if I lie.

Other Posts in Japanese Sumitsubo Inkpot Series

The Japanese Sumitsubo Inkpot 墨壺: Part 2: The Classic Version and the Modern Variant

The purpose of literature is to turn blood into ink.

T.S. Eliot

This is the second article in our series about the Japanese Sumitsubo.

We’ve discussed this tool before, but this time we will examine historical examples as well as an example of an actual sumitsubo ink pot (墨壺 pronounced sue/mee/tsu/boh) currently in your humble servant’s possession. Certainly not a comprehensive explanation by any means, but hopefully it will be informative and mayhap even interesting.

Although the Western chalkbox is now available in Japan, and the Japanese version of this tool is a big improvement over the ones my father taught me how to use when I was a slender “ute,” in Japan the inkline has only been augmented, not replaced, by the chalkbox.

Let’s begin by considering if the sumitsubo is a tool of value to the professional woodworker.

Why Use a Sumitsubo?

Carpenters, woodworkers, steel fabricators, masons and those in many other trades need to mark straight lines for layout and cutting purposes, but what is the longest line one can accurately make using a steel or aluminum straightedge? 1 meter? 4ft? Do you own a truly accurate 1 meter long straightedge or a 4ft long drywall square? How much did it cost? How fragile is it? Will it fit in your nailbag or tool box?

The laser is becoming more and more practical for layout work, but such electronic tools are still not small, light or inexpensive and certainly won’t leave a permanent line. And they have those pesky and expensive batteries that must be constantly recharged and periodically replaced. Very profitable for the manufacturers, of course, but they inevitably end up as poisonous landfill stuffing. When a permanent line is needed for layout or when making long rip cuts with handsaw or circular saw, the snapline is the only viable portable option.

Indeed, the snapline has been the tool for making long, straight layout lines by humans since before recorded history. Sometimes the line has been coated with chalk or limestone dust, sometimes with red soil dust, sometimes with charcoal dust, and in Asia, with a wet ink made from the soot of burned pine tree sap. But humans have such short memories, so most craftsmen younger than 30 years old have forgotten this tool.

The problem with the chalkbox and dry colorants such chalk, charcoal dust or soil is the wide, fuzzy, unclear line they produce.

By comparison, the inkline snaps a relatively narrow, clearly delineated and easy to follow mark on wood, stone and masonry. Not as perfect as a line drawn with a technical pen, of course, but no wider than a laser line and much better than a chalk line.

The second advantage of the inkline is that the line it produces will never get blown away by wind, or be easily smudged. And if you use waterproof ink, one that can be washed away while still wet but becomes indelible once dry, even rain isn’t a problem. And sumitsubo ink has long been available in many colors, including psychedelic hues. Groovy, man!

Does the inkline have downsides? A few, of course. To begin with, you need to be careful to keep the ink bottle tightly closed so it doesn’t leak. Yea, I’ve done that (シ)。

Next, you need to add enough ink to the inkwell to wet the line but not so much it sloshes out making a mess. To paraphrase the ancient Greek poet Hesiod: “Moderation is good.”

And finally, while it can be minimized or even avoided with caution and practice, using an inkline involves getting a bit of ink on at least one fingertip. Fortunately, the Japanese variety doesn’t stain skin like fountain pen or ballpoint pen ink, but washes off quickly and cleanly.

It used to be that a craftsman had to make his own ink by rubbing a stick of sumi ink on a stone with water, a tedious task. Some miyadaiku carpenters still make the ink they use for the first layout lines on important projects in this time-consuming traditional way as a sort of meditative, purifying ceremony, but nowadays, handy ink that won’t separate or mildew is sold cheaply in sturdy plastic bottles. There are of course other ways for a carpenter to obtain Satori.

In any case, your humble servant believes the sumitsubo to be a tool with concrete advantages diligent craftsmen should consider for the toolkit they carry along the sawdust and shaving-strewn path to woodworking enlightenment.

Let’s next next turn our attention to the main subject of this post, the classic, hand-carved wooden sumitsubo.

A Couple of Antique Styles

Not long ago the sumitsubo was a tool each craftsman made for himself by his own hand, giving him incentive to use unusual, even fanciful shapes as an expression of his personal woodcarving skills and artistic sensibilities. Can you judge the skill of the craftsman by his tools? Perhaps not, but it is human nature to do so nonetheless.

Besides the shapes shown in this article, wooden sumitsubo have often been made in the image of animals such as squirrels, rabbits and frogs, insects such as snails and grasshoppers, and even vegetables and plants, not to mention religious images and mythical shapes such as dragons or baku. Many were made to resemble musical instruments such as the three-stringed shamisen, or even boats. Human imagination combined with willing wood and sharp cutting tools can produce fun things.

A variety of hand-carved antique sumitsubo

In the next section we will examine three historical styles that more-or-less illustrate the development of the tool over the centuries.

The Split-tail Sumitsubo

The first style your humble servant would like present is called the “Split Tail” sumitsubo shown in the image below. We discussed this well-preserved example in this post.

I have never owned or used this style of sumitsubo, but friends who have tell me that the excellent air circulation it provides to the reel and resulting mildew reduction is its biggest advantage.

Despite its unique appearance, this style is obsolete for good reasons. Its first design problem is the small inkwell not suited to easy use with a sumisashi pen. And then there’s the total lack of a waist making it easy to fumble. And don’t forget the relatively weak legs and fanciful details easily damaged if the tool is dropped.

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The so-called “Split-tail” sumitsubo. This example is estimated to be nearly 700 years old. Notice the metal ring located in front of the reel intended to facilitate using the tool as a plumbline of sorts.

The “Ichimonji” Style Sumitsubo

The second style of sumitsubo we will examine is a simpler, more compact one called “ichimonji” 一文字, which translates directly to “The character one” and refers to the shape of the tool being a simple line as in the number one, or “一” as it is written using the Chinese character.

A modern ichimonji-style sumitsubo in daily use in the workshop. A simple, elegant design easily fabricated. I know a miyadaiku who uses a similar tool daily in the temple construction work he performs in his workshop.
An antique ichimonji-style sumitsubo. The inkwell was replaced with a wooden insert sometime in the past, probably to deal with ink leaking from the crack visible on its side.
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Another antique ichimonji-style sumitsubo with tasteful gold-leaf decorations. A compact, simple, and attractive version of this ancient tool.

This antique style is compact, easy to make, visually uncluttered, classy and appealing to many craftsmen that make their own sumitsubo, even nowadays. But it too has fallen out of general use for good reasons.

Like the split-tail, the ichimoji sumitsubo has a slab-sided body and no waist making it clumsy to grip in one hand, fine inside the workshop but less than ideal on a construction jobsite.

Another problem is the tiny inkwell which runs out of ink quickly and is clumsy to use with a sumisashi pen.

The reel is obviously on the small size too holding less line than is sometimes needed.

And notice that more than half the reel’s surfaces are enclosed within the body, and that the body has no piercings to encourage air circulation, making mildew growth a problem. At least that was the case before the advent of commercial mildew-resistant ink.

Despite these shortcomings, it is a style appropriate to a workshop environment where the lines snapped are shorter, fumbling is not a concern and the smaller size is useful.

The Genji-style Sumitsubo

A side view of my hand-carved Zelkova wood Genji sumitsubo. Seen from this angle, the crane carved into the prow does not pop out, but his right wing wrapped around the hollow inkwell is clearly visible. The crane is looking towards the heavens, while the angry-looking turtle with his long kilt of seaweed is focused more on keeping the inkline under control, evil pixies at bay, and Murphy feeling hung-over. He’s a serious little fella not prone to small-talk. In Japanese mythology, storks and turtles are considered extremely lucky creatures with the crane said to live 1,000 years and the turtle 10,000 years.
A view of the sumitsubo’s prow. Please notice the unused blue inkline entering the inkwell from the reel to the right and exiting the inkwell at the prow on the left. Please also notice the ceramic thimble inlet in the end of the tool through which the inkline passes and keeps the line from wearing a large hole in the wood. There is a similar thimble where the line enters the opposite end of the inkwell. Sometimes these are made of brass, and other times glass, but fired ceramic is considered the best material for the job. A sumitsubo without thimbles simply won’t last.

The sumitsubo in the photos above and below was hand-carved from zelkova wood (keyaki 欅), a wood popular in Japan for architectural work, carving and furniture. Most exposed woodwork seen in Buddhist temples in Japan is zelkova. It has a pronounced grain, nice color, carves nicely, and is fairly rot-resistant, although not nearly as much as Hinoki, the wood preferred for Shinto shrines. The brandname of this example is “Tsubo Gen” 壺源 .

Back in storage in the US I have a medium-grade wooden Genji sumitsubo I bought in Japan and used for many years, but I purchased the tool pictured here in Tokyo 9 or 10 years ago and have not used it at all, as you can tell from its pristine condition.

It was finished with lacquer when I purchased it so I refinished it with Cashew brand natural urethane last year just for vanity’s sake.

I normally mount this tool inside the lid of my toolchest to please the eye, attract good luck, and fend off malevolent iron pixies. It has accomplished these tasks well probably due to the noble efforts of the scowling little turtle; The crane doesn’t seem to impress them, I fear. We will discuss the lucky aspects of this tool below.

This is a Tokyo version of the Genji sumitsubo as witnessed by the brass crank used for spooling in line. In Western Japan, cranks are not as common, so craftsmen pass the palm of their hand over the top of the reel to spool in line. I’m not sure which style is most efficient.

It is a clever design evolution that resolves the shortcomings of the older designs. I see the following six advantages in this design.

The first advantage to the Genji design is the narrower waist between the reel and inkwell that makes it much easier to securely grip the tool in one hand while at the same time tensioning the line or even braking the reel with the same hand. This is a huge improvement over all older styles.

The second advantage is the wider, larger-capacity inkwell which stays wetter longer and makes it easy to use with a sumisashi for applying layout and designation marks on timbers. It also provides a stable place to rest the sumishashi when not in use without setting it down in the dirt or stuffing it in a nailbag pocket (and making everything else in the pocket wet with black ink).

The third advantage is the larger-diameter inkline reel which contains more line while at the same time being quicker to reel in.

The fourth advantage to this design is the improved air circulation to the line stored on the reel thereby reducing mildew growth. Not only does the wooden reel project further out of the top of the body, but it is also pierced with carved spokes exposing the sides and even the underside of the line on the reel. In addition, the body is pierced at the sides and even the underside to further improve air circulation and reduce weight.

The fifth advantage is that, despite the larger-capacity inkwell and reel, much unnecessary material has been carved away making the tool relatively lighter in weight.

And finally, the sixth advantage of this design is the lucky symbols frequently carved into the body. We all need a little luck.

Typical of many things Japanese, a lot of thought went into these subtle design improvements.

Propitious Symbology

The Japanese Tancho Tsuru crane

One of the most common lucky symbols in Japanese mythology is the crane, said to live 1,000 years and bring good luck, prosperity and happiness. The Japanese love these tall cranes with their little red caps and graceful mating dances. Here’s a link to an interesting video about them.

The turtle, especially the sea turtle, is also considered extremely lucky but for a longer 10,000 years. The turtle carved into sumitsubo usually has a trailing skirt of seaweed flowing from its shell, as does mine, evidence of its great age and accumulated wisdom.

Dragons, Chinese Lions, Baku and other mythological creatures of good fortune are also used.

I’m not a superstitious guy, but I’ll keep my crane and scowling turtle close by just in case, thank you very much.

The components of the typical Genji-style sumitsubo. The body, shown from above, is in the lower half of the photo. The inkwell is coated with a shiny elastomeric polymer to prevent ink from soaking into the wood. The blue polyester line can be seen passing through inkwell, exiting at the prow where it connects to an ebony “karuko” with a steel needle at the far left. When in-use, the pristine natural-color silk wadding above the body is stuffed into the inkwell where it surrounds the inkline. When soaked with ink, this wadding shrinks in volume to half, and wets the line as it passes through the inkwell. The inkline and wadding in this photo have never been used and so are not blackened with ink. The reel, carved with pierced spokes in imitation of the classic Japanese wagon wheel motif, is above and to the right. Notice how the inkline is exposed on both sides and towards the center of the reel improving air circulation and reducing the growth of mildew, not a real problem with modern commercial sumitsubo inks. The brass insert in the reel’s side receives the threaded end of the crank, connecting reel to crank and retaining the reel in the body. The spring on the shaft of the crank is one I had laying around the shop that I added to take up slop, but it’s actually unnecessary. Easier to disassemble than a Glock 19.

The First Modern Variant: The Plastic Sumitsubo

An economic and durable plastic version of the Genji sumitsubo.

The first sumitsubo I owned I bought in the city of Matsuyama on Shikoku Island in 1978. Having few funds, I was unable to afford the hand-carved wooden one I admired, so I bought a plastic version of the Genji-style wooden sumitsubo identical to the photo right.

Being made of plastic using molds from a hand-carved wooden model, it looks exactly like the traditional wooden sumitsubo except for the color, texture and weight. Offsetting the marvelously unsatisfying feel in the hand, this tool has several serious advantages.

The first advantage is its low cost. It can be purchased new for around ¥2,100.

The second advantage is the toughness of plastic. A wooden sumitsubo will at least be dinged and dented if dropped and may even break, but this one will take a likin and keep on tikin. I have seen one survive being run over by a truck.

The third advantage is the certain fact that the inkwell will never develop cracks or leak, unless you notch it with a circular saw or melt a hole in it with welding sparks (yes, I’ve seen that done too (シ)).

And it still has the elegant lucky crane to bring happiness and productivity and his snappy little turtle buddy to keep Murphy away. What more could you want? Egg in your beer?

The classic wooden sumitsubo may not be the most practical tool in the field, but it is the one selected by master carpenters when doing layout, not only because of the tactile experience it provides, but because the tool reflects on the craftsman that uses it. Face it, like a light-blue polyester leisure suit worn with white belt and white shoes, the plastic sumitsubo may be practical but it is simply undignified.

We will discuss some other Modern Variants in a future post.

How to Use the Sumitsubo

The image below is not only historical, but instructive in ways to use the sumitsubo. It depicts an ongoing construction project at the Kasuka Shrine during Japan’s Kamakura period (1192~1333) where carpenters are preparing lumber and timbers to be incorporated into the shrine.

An excerpt from the “Kasuka Gonge Genki E” scroll.

Please notice the “Split-tail” sumitsubo resting on the ground near the feet of the carpenter on the bottom-left, and in the hands of both carpenters to the right.

The team of two carpenters in the lower half of the image are using an adze to keep the log from rolling away and their squares to layout plumb lines on both ends of the log. The carpenter on the bottom right is orienting his square in the vertical direction by squinting at a plumb line made using his inkline and sumitsubo, while the carpenter at the bottom left is matching his square to that of his partner by sighting along the horizontal short tongue of his square. Winding sticks? We don’t need no stinkin winding sticks!

In his right hand you can see the bamboo sumisashi ink pen he is using to mark the plumb line, not doubt with ink from his sumitsubo’s inkwell.

The carpenter and his helper in the upper half of the image are using a sumitsubo to mark the edges of a split plank. The scruffy helper at the left holds the line in place to a mark, while the carpenter in the fancy hat lifts the line with his fingertips and releases it to snap a line of ink onto the plank.

Maybe it’s his hat, but he appears to be laughing like a maniac at some joke I wish the artist had recorded in this image since there is so little humor left in our dry-as-dust politically-correct world ruled by willfully brain-dead, corrupt zombie scolds. No doubt Gentle Reader has met a few of these zombie scolds who tried to suck every ounce of joy from him. Never fear, because I am convinced friend crane and friend turtle can discourage them from climbing the tree to get at us.

The steps to using the wooden sumitsubo are described in the photos below.

One adds ink to the inkwell from a plastic bottle of commercial ink as shown in this photo. The sumishashi ink pen is resting securely across the crank with the wider business end in the inkwell. In this position, one can carry the sumitsubo and sumishashi securely in the left hand with little risk of fumbling or dropping either tool. An excellent design!
The bamboo sumisashi pen is indispensible not only for operating the sumitsubo but for also marking layout and designations on boards and timbers. In recent years, pencils, ballpoint pens and capless marking pens have become popular for these marking tasks. An important role of the sumitsubo is to retain the sumisashi pen in a handy orientation when the sumitsubo is not in use, as shown above. This sumitsubo was carefully designed specifically to retain the pen in-place as shown, and my scowling little lucky turtle considers it his job to keep the pen from running off and getting lost. He hates pixies with a deadly wrath, BTW, and has snapped off the legs, wings, arms and even the heads of many of the pernicious creatures who were bold enough to get within reach of his jaws. I think you’ll agree he does a great job, and never complains. And because of his natural lucky powers, Murphy can’t interfere.
The first step is to wrap the inkline around the needle in the end of karuko. Please note that the line in this photo is dry. When making an actual snapline, the inkline must be wet with ink.
Next, push the sharp needle into the wood to be snapped with the line carefully aligned with a mark. No mark is shown in this image, but if snapping an actual line, one makes the mark first.
This sumitsubo in this photo does not contain ink and so the raw silk wadding is still white and fluffy and the line is blue, but ink is of course necessary to actually snap a line. To persuade the line to soak up ink, one must press down on the wadding and the inkline simultaneously with a sumisashi pen as the inkline passes through the inkwell and out the hole in the prow. The sumisashi and sumitsubo are a team. One controls the tension on the line by pressing the heel of the left hand against the side of the reel, or the pinky finger against the underside of the reel, an operation the design of the Genji-style sumitsubo makes easy, unlike earlier styles. I have my right hand on the crank in this photo, but that was just to take up extra line. To spool out wet line, simply pull the sumitsubo away from the karuko and its needle as the crank spins free, while controlling the tension on the line with the heel of the thumb, and simultaneously pressing down on the line/wadding with the sumisashi. There are two ways to manipulate the sumisashi at this point. Some people hold the sumitsubo in the left hand and pull it to spool out line while using the right hand to press the sumisashi down on the line/wadding. Many people prefer smaller sumitsubo, but the kindly gentlemen that taught me how to use them insisted that the sumitsubo’s inkwell must be large enough and shaped so that the sumisashi can be laid across the line, pressed onto the line /wadding, and securely retained in this position by the left thumb alone as the line is spooled out, as shown in this photo, leaving the right hand entirely free to control the inkline and/or the board being snapped. It’s also much safer when working at any height. Give it a try and you’ll see what I mean. The Genji style sumitsubo is the only one that makes this more efficient and safer technique possible, entirely by design.

Here are links to a few GooberTube videos of guys using sumitsubo. My old master would have been disappointed with their techniques, especially with how they let the sumishashi get in the way, with one guy even sticking it in his mouth to free his hands (egads!). But there’s no denying they are getting the job done. Video 1, Video 2.

Both of these gentlemen are using sumitsubo without cranks, strongly suggesting they are located in Western Japan and not the Tokyo area.

I’m sure Gentle Reader will agree that the hand-carved wooden sumitsubo adds class and dignity to a craftsman’s work, and maybe even a little good luck.

In the next post in this series about the Japanese sumitsubo we will take a look at the most recent evolution of the tool. They look like something designed by Cylons, but they are serious, effective tools nonetheless.

Until we meet again, I have the honor to remain,

YMHOS

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 all Gentle Readers using the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, thuggish Twitter, nor an Assistant Director of the FBI and so won’t sell, share, or profitably “misplace” your information. May my scowling lucky turtle nip notches in my fingers if I lie.

Other Posts in Japanese Sumitsubo Inkpot Series

A Few Masterpieces

“Living by faith includes the call to something greater than cowardly self-preservation.”

J.R.R. Tolkein

In this post your humble servant will present a few modern masterpieces of the blacksmith’s art produced recently by a single craftsman. I hope you are as thrilled as I am to know there is at least one craftsman left in the world that can produce chisels of this quality.

The Blacksmith

The craftsman that made these chisels is very unusual in that, unlike the frantically self-promoting, technically mediocre Hollywood blacksmiths such as Tasai, Funatsu, Kiyohisa, and the modern Chiyozuru gang, he is reclusive and shuns attention. Accordingly, I have been requested to not share any personal details about him, so please don’t ask. The fact is I don’t even know his real name just the brand he uses.

I won’t discuss why he is reclusive, but I will go so far as to say that he is self-employed, well-known in his chosen field, and that chisels are not his primary work product but only a sideline. He makes no more than 5 chisels monthly.

His business philosophy and blacksmithing techniques are interesting so I will share some details about them. He has four strict requirements that a Customer must satisfy before he will accept an order. The first two are business-related, and the last two are about the Customer.

  1. The Blacksmith sets the delivery schedule. Period.
  2. The Blacksmith sets the price. Period
  3. The Customer must be a professional worker in wood who needs and will use the tools the Blacksmith will forge daily. His track record must be independently verifiable. Amateurs and/or hobbyists, regardless of their skill levels, need not apply. Collectors are specifically unwelcome.
  4. Besides being expert in the use of chisels, the Customer must have a minimum level of skills, including the ability to make chisel handles and cut a high-quality Japanese plane block using only hand tools. Once again, this must be verified before an order will be accepted.

Your humble servant commissioned a few chisels from the Blacksmith many years ago and went through this same qualification process, although I didn’t realize it at the time.

The quality of his forging and heat-treat technique is unsurpassed producing a crystalline structure in hard steel that will take an extremely sharp edge, will hold that edge without easily dulling, chipping or rolling while cutting a lot of wood, and is easily sharpened.

But it is his metal shaping and finishing skills that are so awe-inspiring. Please notice the straightness and cleanness of the lines and planes, as well as the uniform and smooth curvature at the shoulders, and perfect symmetry. If Gentle Reader is unimpressed, I encourage you to make a full-scale model from cold wood before trying it in hot metal. I promise you will be convinced.

The Blacksmith uses only “free-forging” techniques, and does not employ the rough shaping dies other modern blacksmiths rely on to improve production speed. His forging technique is so sublime that the entire chisel is shaped to nearly final dimension by fire and hammer, not grinders and belt sanders.

He finishes his products using only hand-powered scrapers (sen) and files.

The performance of Blacksmith’s products are equal to or better than those of Kiyotada back in the day, and are more precisely shaped and more beautifully finished than those of Ichihiro (the Yamazaki Brothers) at their very best. They are simply the best chisels that have been made in Japan in the last 70 years.

Let’s take a look at four chisels recently completed for a Beloved Customer in the USA.

34 x 485mm Anaya Chisel

The Anaya chisel is an antique style used for cutting deep mortises and making other joints in large timbers. It is no longer commercially available.

Top view of a Anaya 34x485mm Anaya chisel
Ura view of 34x485mm Anaya chisel
Side view of 34x485mm Anaya chisel

57 x 485mm Anaya Chisel

42 x 490mm Bachi Nomi

The Bachi nomi is the equivalent to the fishtail chisel in English-speaking countries. The word bachi comes from the splayed tool used to play the 3-string Japanese shamisen, a banjo-type musical instrument. Here is a link to a video of two ladies using shamisen and bachi to perform a famous traditional song in Tokyo.

The Bachi nomi excells at getting into tight places to cut joints with acute internal angles such as the dovetail joints that connect beams to purlins.

There are several ways to resolve the angles at the tool’s face, but in this case the Beloved Customer and Blacksmith agreed on the most difficult, rigid and beautiful solution, the shinogi. This design has the advantage of maintaining a shallower side-bevel angle from cutting edge to neck return providing better clearance in tight dovetail joints.

The handwork performed on this chisel’s face is simply amazing, but the hollow-ground ura is even more spectacular to those who know about this things.

54 x 540mm Sotomaru Incannel Gouge

The Sotomaru or incannel gouge is a strong and convenient chisel used for cutting joints in logs and rounded members on architecture. More information can be found at this link.

This is an especially beautiful example as seen the symmetrical confluence of planes and curves at the shoulders.

Conclusion

I hope Gentle Reader found this post informative. You will never find better examples of the Japanese blacksmith’s art outside of one particular museum. It is exciting to consider that there is still one craftsman alive that can routinely perform this level of work.

While your humble servant has praised these chisels and the blacksmith that made them highly, please do not make the mistake of assuming that I am soliciting orders, or even suggesting that commissioning them is possible, because they are simply not available at any price. Please don’t ask.

YMHOS

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 thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. May my ootsukinomi roll from my workbench and land cutting-edge down on my toes if I lie.