Category: Using Chisels

The Best Striking Chisel for the Job?

A 48mm oiirenomi by Hidari no Ichihiro

When you want to help people, you tell them the truth. When you want to help yourself, you tell them what they want to hear.

Thomas Sowell

A couple of questions prospective Beloved Customers frequently ask your humble servant is what variety Japanese chisel(s) they should purchase, and the best width(s).

In this article I will summarize the answers I most often offer, and list the advantages and disadvantages of 3 types of striking chisels. Perhaps it will be informative.

I started using Japanese chisels long before the internet was more than a group of linked university library research computers. I’ve learned a few things on the subject from Japanese language books over the years, but I’ve yet to read anything on the internet that was more than a regurgitation of marketing screeds and BS from self-proclaimed experts. Most of what I know about Japanese chisels I learned from Japanese blacksmiths and professional woodworkers in Japan, and from my own hands-on, trial and error experience using them to make a living.

Even after the internet expanded (or rather blew up like a dynamited outhouse) into world wide web we know nowadays, there was very little useful written information available in the English language anywhere regarding the varieties of Japanese chisels and how to maintain and use them. This frustration was my primary reason for establishing this website, in fact. But after starting this humble website I’ve noticed more and more people presenting themselves as experts on the internet who merely imitate, indeed plagarize, what I’ve written. Do they do this to improve general knowledge on the subject of Japanese chisels, or do they have other motives?

Posers and copycats are fine, but many lack the true understanding that only comes with hands-on experience under pressure. I encourage Gentle Readers to seek useful knowledge based on practical experience rather than ill-informed click bait.

Regarding my answers to the two questions listed above, let’s begin by considering the options I believe most likely to serve Gentle Reader best.

As this article: The Varieties of Japanese Chisels explains at length, there are two primary types of Japanese chisels: the tatakinomi striking chisel and the tsukinomi paring chisel. In this article we will examine only tatakinomi.

A 42mm oiirenomi by Sukezane

Tatakinomi (Striking Chisel)

The three types of chisels described below are categorized as “Tatakinomi” which translates directly to “striking chisel.” It’s name’s derived from the way one motivates it by “striking” the butt of its wooden handle with a steel hammer. No, not an inefficient, imprecise wooden mallet but a serious, differentially-hardened, high-carbon steel tool.

What is a Gennou Hammer?

Hammers to Use With Chisels Part 2 – Hammer Faces

Head Style & Weight

Tatakinomi are the best-known type of Japanese chisel, but there are other kinds, primarily “usunomi” or paring chisels.

Because high-quality chisels are not free, and because the powerful forces applied to tatakinomi place it at risk, it’s important that those you procure be durable, so let’s next consider consider some factors impact that always govern a chisel’s durability.

Keys to Chisel Durability

High-quality, hand-forged (vs. stamped, mass-produced) Japanese striking chisels differ from Western-style chisels in that they are intended to be wacked hard all day with a steel hammer, treatment that will quickly destroy Western chisels, but which professional-grade, handmade Japanese chisels eat with chips and beer.

But why can our tataki chisels shrug-off abuse that would destroy all other chisels? There are three primary reasons. First, the handles are made of either Japanese red oak or Japanese white oak, varieties of hardwood native to Japan significantly denser and stronger than all species of American and European oak.

The second reason is that the handle is reinforced by a steel ferrule in the shape of a hollow “truncated cone,” called a “kuchigane,” which translates to “mouth steel,” carefully fitted to the contoured blade end of the handle.

This component doesn’t just perch on the handle like a pelican on a post but squeezes and compresses the wood fibers around the tang of the blade making it nearly impossible for the impact forces of a hand-operated hammer to split the handle. In fact, the harder the handle is struck the tighter the kuchigane becomes, the more constraining hoop pressure it applies to handle. This is a genius design detail, one commonly found in many ancient weapons (swords, spears, and pole weapons) around the world, BTW. I’ll be dipped in chocolate and sold as a hairy truffle if I can figure out why European and America tool makers abandoned this technique a hundred or so years ago. Perchance an early example of enshittification?

The third reason the handles of hand-made Japanese chisels can eat up such abuse without getting ulcers is a piece of furniture called the “crown,” what some people vulgarly call the “hoop,” a steel band with a particular cross-section encircling the butt end of the handle. If the crown and handle are fitted properly (the majority of Japanese chisels sold overseas are not, BTW), this crown will apply tremendous hoop force on the wood preventing it from splitting.

An important detail worth knowing is that this crown doesn’t just sit on the handle like a metal hatband, but is designed to slowly move down the length of the handle as the handle becomes shorter over the years providing continuous support for the handle without the need for future adjustment. Ergo the nickname “sagariwa.” Clever stuff.

Another less-obvious reason high-quality chisels can happily endure such abuse is the fact that the handles are hand-turned of dense, well-dried, defect-free Japanese hardwood, and hand-fitted to the blade by an experienced Japanese craftsman who specializes in making handles (Mr. Hasegawa, in our case) with many years of experience, to ensure a proper fit between wood and steel components. Such handles cannot be procured in bulk from Chinese farmers. Why does this matter? A sloppy fit between steel and wood will not only reduce a chisel’s useful lifespan, but will actually reduce its efficiency.

The Three Types of Tatakinomi

Let’s next consider the three main types of tatakinomi, the oiirenomi, hantatakinomi, and atsunomi.

Top: 48mm mentori oiirenomi chisel. Sukezane brand OAL = 222mm, t = 8mm, wt = 226gm Center: 48mm mentori hantataki chisel. Nagamitsu brand OAL = 270mm, t = 9mm, wt = 356gm Bottom: 48mm Mentori atsunomi chisel. Sukemaru brand OAL = 295mm, t = 11mm, wt = 426gm All 3 chisels are fitted with Japanese white oak handles and black furniture

The Oiirenomi Chisel

The most popular type of tatakinomi striking chisel sold nowadays is the mentori oiirenomi, pronounced oh/ee/reh/noh/mee). This is the Japanese chisel best known outside Japan. A couple of variants are the older-style kakuuchi oiirenomi and the slimmer shinogi oiirenomi.

The oiirenomi is a smaller, lighter, more economical version of the bigger, older atsunomi style chisel. Just as I have done so often in answer to questions from prospective Beloved Customers, I’ve compared some of the key advantages and disadvantages of the oiirenomi compared to the hantataki and atsunomi below. Horses for courses.

Oiirenomi’s Advantages:

  • More compact (shorter and slimmer) than the atsumomi and hantataki chisels, the oiirenomi is extremely handy for making light cuts in tight spaces, for making furniture and cabinets, and doing installations. Being less bulky, oiirenomi take up less space in the toolbag/toolbox, and accordingly are easier to transport to and around the jobsite.
  • The oiirenomi’s lighter weight, compared to atsunomi and hantataki, makes them easier for those with weaker hands to use.
  • Oiirenomi can be motivated with a lighter hammer and/or less force for more precise work in some jobs.
  • Less costly than atsunomi and hantatakinomi.

Oiirenomi’s Disadvantages

  • While compact and lightweight, their blade, neck and handle are shorter in length than atsunomi and hantataki making them unsuited for some deep cuts. This is seldom a problem when making furniture and cabinets, but their shorter reach may limit their effectiveness in some carpentry and timber framing projects.
  • Their reduced weight is achieved by reducing the amount of metal used and employing a shorter handle that some users with large hands sometimes find inconvenient.
  • Most importantly, the reduced weight is achieved by incorporating less metal in the blade, neck and shoulders making the oiirenomi relatively weaker and less durable when subjected to the heavy pounding required to cut the large joints and hog the large volume of wood required when timber framing. For the same reason, wider blades (42mm+) may not be adequately supported by the thinner neck and lighter shoulders of the oiirenomi.

The oiirenomi is perfect for most furniture and cabinetry tasks around the shop, and is very portable for jobsite use, but it may not be suited to heavy carpentry, timber framing or for use by those with humongous hands.

Professionals that use chisels from morning to night, however, prefer the atsunomi for even small jobs simply because it’s stronger, cuts with more authority and lasts much, much longer.

The Hanataki Chisel

The hantataki chisel is a larger, longer version of the oiirenomi, or depending on your viewpoint, a smaller version of the atsunomi. It has both advantages and disadvantages when compared its brothers.

Hantataki’s Advantages

  • Hantataki chisels are an “in-between” chisel built longer and somewhat beefier than oiirenomi chisels, but shorter and lighter than atsunomi chisels, depending on your viewpoint again. They take up less space in the toolbox/toolbag than atsunomi and are therefore easier to transport.
  • Their greater length compared to oiirenomi makes them handier for those with larger hands.
  • Hantataki can cut deeper/longer joints than oiirenomi can.
  • While not as heavy-duty as atsunomi, hantataki are significantly beefier and stronger than oiirenomi and therefore better suited to cutting joints in large timbers using heavier hammers. They make great chisels for carpentry work in the field.
  • Our hantataki chisels are priced nearly the same as our oiirenomi chisels, making them an economic choice.

Hantataki’s Disadvantages:

  • Hantataki chisels can’t cut as deeply as atsunomi, but this is seldom a serious limitation except in timber framing work.
  • While heavier and tougher than oiirenomi they are lighter than atsunomi. Horses for courses.
  • They are not as strong as atsunomi and may be at a disadvantage for some heavy timber framing jobs. Although we carry them in 54mm width, this may be a little too wide for the shoulder to adequately support during heavy use.

The Atsunomi Chisel

Atsunomi (ah/tsu/noh/mee) are the largest standard size chisel. There are special-order chisels with longer necks, such as the anayanomi, for cutting special joints (no longer made), but this is the chisel used for serious, heavy-duty carpentry and all timber framing jobs.

A 54mm anayanomi (a long-necked atsunomi) by Nora. The long neck is for making deep cuts.

Atsunomi means “thick chisel,” which explains it well. As an example, our 48mm wide Sukemaru-brand atsunomi are 295mm long (OAL) 11mm thick, with an 85mm long blade, 70mm long neck, and weigh 426 grams, almost twice the weight of our 48mm Sukezane-brand oiirenomi chisel.

Two of your humble servants well-used chisels by Kiyotada. Top: Oiirenomi with white oak handle. Bottom: Atsunomi with red oak handle.

Atsunomi’s Advantages:

  • Long blade, neck and handle allow this chisel to make deep cuts in heavy timbers, this chisel’s greatest advantage.
  • Thicker blade and neck make the atsunomi much stronger and tougher for hard cutting all day long.
  • The extra mass of the atsunomi cushions the impulse shock acting on user’s hand and wrist joint compared to the same impulse forces acting through lighter oiirenomi or hantataki.

Atsunomi’s Disadvantages:

  • Being bulkier and heavier, transporting atsunomi by bus, train, bicycle or mare’s shank is relatively more work.
  • Their extra mass requires a heavier hammer to motivate in order to make the same cuts as the oiirenomi and hantataki. This requires a greater expenditure of energy,.
  • Being heavier, the user may need stronger hands and arms than when using smaller chisels.
  • Although the extra weight and increased moment of inertia makes the atsunomi more stable than other chisels, it requires greater skill when making delicate cuts.

Blade Width

“What’s best blade width for the job” is another question people always pose, but it’s a a bit more difficult to answer. The following are some points to consider.

First, if you will use the chisel(s) to cut mortises you either need to (1) determine in advance what width mortises you will need to cut; or (2) The likely range of mortises. The difficulty of answering these questions, and the fact that the answer varies from job to job, is why professionals end up owning more than one or two chisels.

But how to decide? If the mortise is fairly narrow, say 6~15mm, then owning a chisel the same width is most efficient. In the case of wider mortises, it’s often best to use a chisel a little narrower than the mortise hole, and then pare the walls to final dimension. Why? Because, unless you’ve had a lot of practice, and your chisel has tight tolerances, it may tend to bind in the mortise hole and maybe even gouge the sidewalls. But by paring to final dimensions, the width of the mortise hole can be kept within tolerances and the sidewalls kept free of gouges.

When all’s said and done, and when speed and precision are critical, it’s best to check, adjust and maintain the tolerances of your chisels.

Another point to keep in mind when planning mortises is that it’s almost always most efficient to match the width of the mortise to the dimension your chisel can most easily, precisely and consistently cut rather than planning the mortise width around some specific dimension, e.g. precisely 6mm. One then cuts each specific tenon to fit each specific mortise instead of some dimension on a drawing. Once you have your chisel setup properly and a mortise gauge with a matching setting, there will be no need to measure mortise width at all.

People always ask what 3 or 4 chisels they should purchase to get started making furniture, for instance. The easy answer is 6, 9, 12, 24mm. Why not wider? I love wide chisels, but if you only have a few chisels, you will need one on-hand that does a great job of paring. 24mm is about the maximum width the average guy can precisely motivate a chisel by hand without using a hammer. Of course, this capacity will vary with the joint being made and the hardness of the wood, but 24mm is standard.

While we’re on the subject of paring, the handles of oiirenomi are too short for a powerful grip and good control with two hands, and the steel crown tends to be hard on one’s hands. For these reasons, the usunomi paring chisel with its thinner, longer blade, neck and handle, and lack of a crown is ideal. If you don’t have any yet, you will find usunomi to be wonderful tools and great friends.

Conclusion:

The oiirenomi is a compact, lightweight, nimble and less-costly striking chisel suited for light cuts with moderate weight hammers. It’s the typical starter chisel for Japanese woodworkers, and the only variety of Japanese chisel most Western woodworkers know. Perfect for making furniture, cabinets, and most joinery. Being lightweight, it will not endure long sessions being pounded on with heavy hammers. Also, being short, it may not be suited for those with large hands.

The hantataki chisel by comparison is slightly larger than the oiirenomi. It’s relatively inexpensive, not especially heavy, and can cut deeper joints. It’s perfect for those with larger hands that find the oiirenomi uncomfortable to use. And it will do everything the oiirenomi can and more.

The atsunomi is the largest, heaviest, strongest and most durable of the Japanese chisels. It’s ideal for heavy work such as timber framing and wasting large amounts of wood quickly. Besides carpenters and timber framers, many professional craftsmen in Japan, even those that never work on construction sites, prefer to use atsunomi even for delicate work because of their relatively longer blades and cost-effectiveness.

Because of its greater size and weight, the atsunomi is not as nimble as the smaller varieties of tatakinomi and demands greater strength and skill of the user. But on the other hand, it’s very stable in the cut, wastes wood with impressive gravitas, and will endure many decades of hard daily use in professional situations without complaining.

YMHOS

A folding screen by Kano Hogai with an ancient plum tree, bamboo, and birds. This screen is a designated “natural treasure.”

The Varieties of Japanese Chisels

The Mentori Oiirenomi (面取追入鑿）

The Kakuuchi Oiirenomi (角打追入鑿）

The Hantataki Chisel

The Atsunomi （厚鑿)

The Usunomi Paring Chisel

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, megalomaniac Meta, or sticky-fingered Apple and so won’t sell, share, or profitably “misplace” your information. If I lie may a Bandersnatch fruminate all over my face!

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New Ootsukinomi Paring Chisels

Envy was once considered to be one of the seven deadly sins before it became one of the most admired virtues under its new name, ‘social justice’.

Thomas Sowell

We’ve recently received a long-awaited (and we feared long-forgotten) order of two-handed Ootsukinomi paring chisels from our blacksmith. This post is a simple show and tell.

Your humble servant has scribbled about this tool in this article in our series about the varieties of Japanese chisels

Ootsukino, pronounced oh/tsuki/noh/mee, are large, long-handled paring chisels, the equivalent to the “slick” in the US woodworking tradition, a standard tool for timber framing. It is a rare chisel nowadays, and difficult to make.

This chisel is never struck with a hammer, but is pushed two-handed to pare surfaces and joints in wood to final dimensions. The long handle provides much greater angular control and precision than a standard paring chisel, while the ability to grasp it firmly in two hands makes it possible to effectively employ the greater power of one’s back and legs.

We also carry Mr. Usui’s Sukemaru-brand ootsukinomi, but after looking for a less-expensive option for our Beloved Customers, we ordered these from our Nagamitsu blacksmith over five years ago. Soon after placing the order we despaired of them ever being completed due to the difficulty of forging and shaping them in his advanced years, and did not want to pressure him. But we were surprised to learn recently, indeed after he had retired, that he had actually made significant progress on nine 2-piece sets, lacking only sharpening and handles, and so arranged for them to be completed. At long last they have been delivered.

Yes, this variety of chisel can be procured individually, and Mr. Usui of Sukemaru fame has been kind enough to fill many special orders to meet specific requirements of our Beloved Customer. But the standard way to purchase these in Japan is a 2-piece set, one chisel in 42~54mm blade width and the other in 24mm. We had these forged in the most common 48mm and 24mm boxed sets.

The overall length of both chisels is approximately 640mm (25-13/16″) with a 140mm (5-1/2″) long blade, 160mm (6 -19/64″) neck, and a 340mm (13-25/64″) handle made of an attractive grade of dark-red Japanese red oak. Both chisels have a standard, nicely-formed single ura with the hardened steel lamination properly wrapped up the blade’s sides for the extra toughness and rigidity essential to this tool.

A triple-ura on the 48mm chisel is a useful feature, and we have had Mr. Usui forge his chisels with this detail, but it would have added quite a bit to the cost and so is not available in this more economical brand.

The 48mm chisel is used for paring wider joint surfaces, the cheeks of tenons, and the interior side walls of mortises. It’s the standard mentori beveled-side design seen in our mentori oiirenomi, hantatakinomi and atsunomi.

The 24mm chisel is forged in the shinogi style with a more triangular cross-section to provide clearance for the blade in tight places to pare the many dovetail joints used to attach beams, purlins and bottom-plate (土台) timbers, as well as the end walls of the many 24mm mortises commonly found in traditional timber framing work.

These are not mass-produced tools but hand-forged in Japan from beginning to end by a highly-experienced blacksmith in his one-man smithy using Hitachi Metal’s Yasugi Shirogami No.1 high-carbon steel (White Label No.1 steel), famous for its superior sharpness, ease of sharpening, and sharpness retention performance for the cutting layer, forge-laminated to a softer low-carbon steel body and neck for toughness, typical of all our Nagamitsu-brand products.

These are nicely shaped and finished, top-quality, serious chisels for serious work, but are not suited to everyone. While joiners that make large doors and panels often have a set in their workshop, most cabinetmakers and furniture makers will seldom need such large chisels. But they are one of those tools that when you need them, nothing else will do. Indeed they are indispensable for cutting precise joints in large timbers and joinery, even when those joints are hogged-out using electrical equipment.

At this reduced price, We only have a few sets looking for new masters who will feed them lots of yummy wood, so if you are interested, please contact us using the form below.

YMHOS

SONY DSC

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. If I lie may every spoonful of burgundy cherry ice cream I ever eat taste like dirty truck tires.

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8 responses to “New Ootsukinomi Paring Chisels”

  1. Gary Avatar
    Gary

    Very nice, Stan. I have a couple of similarly sized ootsukinomi. Besides large joinery, I find that picking one up and waving it around is useful for chasing people out of the shop. It gets their attention.
    I have a question about sharpening these. I know that it is easier to remove the handle for sharpening the blade. But after a few rounds of this the handles have become too loose. I have added paper shims inside the mortise for the tang, but that seems a short term solution. Is there a better long term solution, or should I just continue to add shims?

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    1. covingtonandsons Avatar
      covingtonandsons

      Thanks for your comment, Gary! I have never waved an ootsukinomi at, or used one to chase away, people, politicians or even pixies (descending order of humanity), but it sounds like a fun time was had by all. Please send link to video! (ツ) An ootsukinomi with a loose handle is extremely irritating, and if it becomes loose enough for the blade to separate from the handle on it’s own at an importune time that pervert Murphy may have a wonderful time dancing naked in puddles of red sticky stuff (sorry, no video). So while I don’t recommend routinely removing the handle after the initial sharpening, I do recommend using a honing jig to help maintain the proper bevel angle on the stones. Most people use a large block of hardwood cut at an angle and inlet to fit the chisel’s face for stability. When the wood becomes worn and the angle skewampus it can be refreshed with a thin angle-cut on a table saw, or maybe a pass or two on a jointer. I suppose the commercially-available jigs like the Lie-Nielson widget (perhaps with jaw extensions?) would work too and last longer, but whatever method used, it requires more physical effort and concentration than a shorter chisel does. Looking forward to the video! Stan

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  2. Gary Avatar
    Gary

    Thanks, Stan. I have a little sharpening widget that fits the blades but the long handle makes using it awkwardly unbalanced. I’ll go with a shop made hardwood fixture. And I’ll work on that video.

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    1. covingtonandsons Avatar
      covingtonandsons

      You’re right of course about how awkward and over-balanced the handle makes the process. Two options for the block. The first is moving the block/chisel on the stationary stone, and the second is to clamp the chisel/block down and move the stone over the blade’s bevel. The latter takes gear and time to setup, but perhaps yields better results with less risk. 2 drachma.

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  3. Bruce MILBURN Avatar
    Bruce MILBURN

    COVINGTON & SON

    To your humble servant from another humble servant. Let’s not argue our spiritual merits! I enclose a couple of photos of a chisel I sadly only use occasionally. I’m too ignorant to identify its origins but it feels good in the hand when working or not. You might enjoy! Yours Bruce Milburn (convictions in darkness)

    Sent from my iPad

    >

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  4. The Lost Scrolls of Handwork Avatar
    The Lost Scrolls of Handwork

    I’d like your opinion on this brand of Japanese waterstone, Ikeda, which has 10 000 grit. Is it all the vendor has made it out to be? I’m thinking of switching from a strop to a 10,000 grit stone . There are several reasons why I desire to change. The most accurate response is that I’ve always been interested in higher grit stones and am eager to compare them to strops.

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    1. covingtonandsons Avatar
      covingtonandsons

      Sorry, I don’t have experience with the Ikeda stones. I suggest you beware of hype related to stones, especially if costs are high.

      Liked by 1 person

      Reply
      1. The Lost Scrolls of Handwork Avatar
        The Lost Scrolls of Handwork

        Thanks for your quick response. The costs for everything is too high, but it’s on special $150 down from 200. Basically, it’s down to what it was originally priced a year or so ago. On average, the 10k grit stone irrespective of the brand is priced around $150-200

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The Mystery of the Brittle Blade

There are few blessings without a curse hidden inside, nor curses without a whiff of blessing. Like most things, it’s a matter of how you look at it.

Joe Abercrombie, Isern, “A Little Hatred”

In this article your humble servant will attempt to shed more light on the ancient “Mystery of Steel.”

This story does not begin on a dark Scottish moor, nor on a foggy London night in a drawing room with the door inexplicably locked from the inside concealing bloody mayhem splattered across intricately carved linenfold oak paneling; Rather, it begins in an ordinary woodworking shop. And it goes something like this.

The Brittle Edge

The curtain rises on a humble detached workshop where, unbeknownst to our victim, an erstwhile woodworker we shall call “Woody,” dastardly events are about to unfold (cue the deep, ominous music). It’s really just an old dilapidated garage, but it’s Woody’s kingdom and he is master here, or so his bench cat allows him to imagine. He’s expecting us, so we’ll just go on in.

Make sure the door is firmly closed behind you now; It tends to stick and Woody’s bench dog loves to jet out and root around in the neighbor’s garbage. No mystery about why they call the fuzzy leg-humper “Stinky.” (ツ)

Pine and cedar plane shavings litter the floor of Woody’s shop and their fragrant aroma fills the air erasing the mutt funk. Autumn sunlight filters gently through the single dusty window as sawdust motes dance above a limp bench cat sleeping at the far end of the workbench dreaming of buffalo wings and big-eyed kittens. All appears well in Woody World.

Woody’s sitting at his workbench on his white Smith & Wesson padded stool where he has just unpacked his new chisel, admired it, checked the fit, finish and edge, and appears quite satisfied. He lays out a test mortise hole on a piece of scrap oak, picks up his gennou hammer (the one with the classic Kosaburo head and the sexy Osage Orange handle that turned out so well), and begins to chop a test mortise. But, wait!… Something’s not right!

With trembling hands, Woody examines the chisel’s cutting edge to discover the last thousandth of an inch or so has changed from smooth and sharp to ragged and dull. “Nooooo!” Woody wails as he lifts his arms to the ceiling, arches his back, and slumps to the floor on his knees in a pose reminiscent of Sergent Elias in that poignant moment on a battlefield in Vietnam; “I have been betrayed!” he cries with wavering voice. Yes, Woody’s a talented and enthusiastic drama queen in the Smeagle mold; Maybe even good enough to run for the US Congress.

Another of Woody’s qualifications for high public office is that he dearly loves to pull a cork, so while he walks to the corner Piggly Wiggly to get a 5th of tequila to anesthetize his emotional shock and refill his thespian fuel tanks, let’s take a load off and sit on his workshop sofa over there while I explain the cause of his emotional fragility. Yep, you’re right; It’s a recycled bench seat from an old Dodge Power Wagon he salvaged from a junkyard and converted to a sofa for watching ballgames and taking naps in the shop away from the jaundiced eye of “She Who Must Be Obeyed.” Don’t worry about your pretty pink dress, princess, it’s just honest sawdust.

With tools, tequila, and the mystery of steel involved, this could be a long story, so let’s consider how to solve this particular mystery before Woody gets back and starts up his caterwauling again.

But just so you don’t become discouraged, let me state right now that while all seems dark and hopeless to Woody now, there’s a tunnel at the end of the light, and he may actually have reason to rejoice greatly! But that’s for later in the story.

The Questions

A Japanese blacksmith fluxing and placing a piece of high-carbon steel onto a hot piece of jigane in preparation for forge-welding the lamination of a blade.

Your humble servant always asks the following questions when someone complains of a chipped cutting edge on a chisel or plane blade. When Woody gets back, and if he manages to remain coherent and vertical long enough, we’ll ask him these same questions. If your blades are causing you grief, you should consider asking yourself these questions too. Jose Cuervo and acting skills are not required.

  1. What sort of quality is your problem chisel/plane? Low? Medium? High? How do you know? This is relevant because a poor-quality chisel/plane will fail just by looking at it too hard;
  2. What type of chisel is it? A striking chisel or a paring chisel? Each type of chisel is used for different tasks and in different ways;
  3. What and how were you cutting when the edge failed? This is important because some woods are best cut in a different manner than others, and some cuts require a special approach if we are to avoid damaging the tool;
  4. What is the bevel angle? If the angle is much less than the ideal for the type of chisel/plane, cut and wood, we may have found the culprit. Finding the perfect angle for your chisel and situation may take some experimentation;
  5. How did the edge fail? Did it crumble? Chip? Roll? Dent? A combo failure (with cheese)? This will tell us a lot about the tool.
  6. Was the wood you were cutting dirty? Did it contain embedded grit? This is an important question because many people carelessly use their valuable chisels, planes and powertool blades to cut hard minerals instead of scrumptious wood. The lesson? Don’t be a slob: Scrub your wood with a steel brush before cutting it. And saw the last 3~4 millimeters off both ends of every board, or at least chamfer the ends with a block plane, drawknife or knife to remove the grit always embedded in end grain, before you put it through your jointer, thickness planner or tablesaw, or cut it with handsaws, planes or chisel. If you have not made a habit of doing this, don your scratchy sackcloth tidy whiteies, smear ashes on your face, then repent and be baptized because you have been abusing your innocent tools, Bubba. Clean your wood and you will notice the difference. Strange that no one I have ever asked this question has admitted to using dirty, stony wood at first. The reason is usually simply that they didn’t realize it was filthy until I pointed it out to them, just as it was pointed out to me many years ago. What’s that you say? You don’t have a stiff steel wire brush in your toolbox?! Shame on you;
  7. Did you abuse the chisel by trying to lever wood out of the cut, a mortise for instance? This is a common cause of failure. People accustomed to using amateur-grade tools with soft cutting edges frequently discover the edge of their new chisel has chipped after using it like a cheap Chinese screwdriver to lever waste, never imagining the harder and more brittle steel of a quality chisel might be damaged. Such boorish behavior voids the warranty on our chisels, BTW, because a chisel is a cutting tool, not a prybar, can opener, or paint stirrer, much less a screwdriver.

Did your answers to these questions suggest any remedial action to you? The best answer to Question 1 is often to procure a better-performing tool.

But if your tool is professional-grade instead of hardware-store grade, then you may need to learn how to use it and maintain it properly. But that is a story for another day.

Let us shift our attention briefly to another, related mystery, one that has more to do with human nature.

Why Are the Blades of So Many Modern Tools Mediocre Performers?

It wasn’t always that way, but there are sound business reasons why chisel and plane blades are such poor performers nowadays, even in Japan, and like many things, it boils down to money as taught by the Harvard School of Business Department of Quality Adulteration. The numbers of craftsmen that routinely use handtools has decreased, and therefore the demand for professional-grade tools is way down. In Western countries the degradation of tool standards started even earlier.

In this situation, and where customer expectations are as high as an earthworm’s vest pocket, mediocre tools are simply more profitable for manufacturers and retailers. After all, low-quality materials are cheaper and it only takes ordinary machines and minimum-wage factory workers, not expensive trained blacksmiths, to make tool-shaped objects from mediocre-quality materials. Professional woodworkers won’t touch such crap, but amateurs, the inexperienced and those bewildered souls who judge performance based solely on lowest cost buy them by the ton.

More now than ever, “sustainability” is given pious, pompous lip-service, while the reality of modern society is that high-volume sales of colorful but poor-quality tools designed to meet planned obsolescence goals, manufactured in lots of thousands by Chinese farmers, and destined to become early landfill stuffing has become the only viable business model left standing. Gofigga.

More importantly, even if they would do better if given half a chance, inexperienced amateurs seldom have anyone to teach them how to use and maintain their tools, so they never learn proper maintenance principles and cutting techniques. When they damage their woodworking tool blades carelessly, they blame the tool supplier for their own failure. As Mr. T would say: “I pity the fool.”

Faced with this sort of consumer, it is simply easier and more profitable for tool companies to manufacture, and for retailers to sell, chisels and planes with softer, tougher, cheaper blades suited to amateurs. I think you can see the vicious cycle.

A kakuuchi oiirenomi chisel by Hidari no Ichihiro
An Atsunomi chisel by Hidari no Ichihiro

A Non-technical Technical Explanation

Your humble servant’s earlier comment that Woody may have cause to rejoice about what appears to be metallurgical malfeasance may cause some Gentle Readers to wonder if I am mad as a sack of owls; Perhaps my most excellent aluminum-foil skull cap (the one with purty curly copper wires) malfunctioned permitting those icky inter-dimensional aliens’ mind-control waves to leak through?

Like our absent drama queen, I too was devastated when first faced with a manifestation of the Mystery of the Brittle Blade many years ago, but I can now explain why it may be sign of a blessing instead of a curse. But allow your unworthy and slothful servant to provide some background and explain some time proven solutions before presenting the good news. Steak before ice-cream, you see.

I beg the indulgence of knowledgeable Gentle Readers who feel insulted by the lack of temperature curve drawings and jargon such as “pearlite,” “martensite” and “ austentite,” and ask them to understand that, while this blog is focused primarily on informing our professional Beloved Customers, many Gentle Readers require a less technical explanation. Simple hospitality demands that your humble servant make an effort to provide useful insight to a wide range of Gentle Readers. As a dude wearing a leather skirt and sandals in a movie once said: “ Are you not entertained?”

A shinogi oiirenomi chisel blade by Hidari no Ichihiro

Quenching the Blade

When a blacksmith quenches a high-carbon steel blade in water in the ancient manner (called “Yakiire” 焼き入れ in Japanese which translates to “burn in” in English), the steel suffers a thermal shock, sometimes severe enough to crack it. This violent cooling also causes a peculiar crystalline structure to form in the metal, one that causes it to become harder and increase in volume, and even to warp to some degree. The casual observer may imagine the water cools the entire blade uniformly, but ‘tain’t so.

Those areas of the blade that cool the quickest form the highest volume of carbide crystals, the bulkiest latticework, and become hardest. In the case of chisels, planes, and kiridashi knives, the end of the blade has the most exposure to water, cools quickest, and therefore becomes hardest, at least during the first quench.

The blacksmith may carefully repeat the heating and quenching process multiple times, sometimes varying the heat time and temperature to achieve the desired crystalline structure and uniform distribution of small, hard carbides that define “fine-grained steel,” but the quenching process by itself always leaves the blade too hard and too brittle to be useful as-is.

Tempering the Blade

Now that the blade is hardened, indeed too hard, the blacksmith must mellow the steel, reducing its hardness while at the same time increasing its toughness by carefully reheating and cooling the steel to modify the crystallized steel in a process called “tempering,” in English and “yakimodoshi “ 焼戻し ( literally “ burn return” ) in Japanese. In this way, a steel blade hardened to Rc85 degrees during the first quench, indeed brittle enough to break into pieces if dropped onto a concrete floor, can be softened to a useful hardness while becoming at the same time much tougher.

In materials science and metallurgy, toughness is defined as the ability of a material to absorb energy and elastically deform without fracturing. To “elastically deform” means an object changes shape or deforms when pressure is applied, but returns to its original shape when the pressure is removed. For example, if you clamp one end of a piece of mild-steel wire in a vise and apply a little force with your hand at the other end it will bend at first and then spring back to its original shape when you remove pressure. This is an example of “elastic deformation.” But if you apply enough pressure the wire will not spring back (“rebound”) but will remain bent. This permanent bend is called “plastic deformation.” Mild steel wire is truly “tough as nails.”

Glass is the opposite case. While it exhibits more elastic deformation than most people realize it can, it will tolerate no plastic deformation, because when the stresses in glass reach the “yield point,” instead of bending plastically, it breaks.

A brittle blade is hard but not tough, and while it will elastically deform a little bit (often so little it’s unnoticeable), it too easily breaks. Proper tempering therefore, is critical to obtain useful toughness.

But this reduction in hardness and increase in toughness brought about through tempering is not always 100% uniform, and as mentioned above, the extreme cutting edge of the blade of a chisel or plane tends to be hardest and therefore most brittle in the case of hand-forged tools, even after tempering. The cheap, mass-production solution is to simply make the entire blade softer, say HRc45 for example, so brittleness will never be a problem. But such a tool is more a sharpened screwdriver than a cutting tool suited to the needs of professional woodworkers, IMHO.

I’m being too harsh, you say? Not even a little bit. A soft blade dulls quickly, wastes the professional woodworker’s time and money, and is irritating instead of useful. Perfect for turning screws, spreading spackle or stirring paint but not much good for quickly and precisely cutting lots of wood for pay, thank you very much.

Solutions 1 & 2

The Mystery we are investigating on Woody’s behalf is as ancient as steel itself. And of course there are reliable ancient solutions our blacksmiths employ. Let’s consider two of them.

First, create a crystalline structure in the blade through hand-forging that is more resistant to fracturing than ordinary steel regardless of its hardness. The difference hand-forging produces occurs in the crystalline structures in the steel and is not visible to the naked eye. It doesn’t happen by accident.

Second, employ painstaking heat-treatment techniques combined with uncompromising quality control to achieve the right balance of hardness vs. toughness.

To help control the heat-treat process, our blacksmiths apply a special mud-like compound to specific areas of the blade to slow down the thermal shock during the quench and improve the steel’s crystalline structure. Every blacksmith has their own “secret sauce,” so I can’t tell you what it contains, but I’m confident there’s no mayonnaise or Tabasco Sauce involved. This technique is not unique to Japan, BTW, but we know it has been successfully used by Japanese swordsmiths for at least 900+ years. I’m confident there were some old boys in ancient Syria and India that had the knack too.

It ain’t rocket surgery, but factory workers in Guangzhou or Mumbai can’t do it even with unlimited supplies of Tabasco Sauce.

So, we have discussed the reasons, and some solutions, but what to do about a blade that’s already chippy?

Solution 3

Assuming the blade has been forged by an expert blacksmith in accordance with the principles outlined above, as our tools are, the fix to chippiness (oops, did I coin a word?) is to be patient and sharpen the blade three or four times thereby removing the extra-brittle steel exposed at the cutting edge, the area that became harder and less tough than the rest of the blade during the heat-treating process. With few exceptions, the blade will then “calm down” and stop misbehaving.

This is the solution we ask our Beloved Customers to employ when this problem infrequently arises. It requires faith, and patience, but it almost always works.

Solution 4

The last solution, and one I certainly do not recommend to anyone except as a last resort, is to heat the cutting edge under a candle flame. Not an acetylene torch; Not a gas stove; Not a propane torch; Not even a butane cigarette lighter; A candle flame only. You want the extreme cutting edge to become just a smidge hotter than you can comfortably touch with your bare finger. Don’t heat the entire blade, just the cutting edge.

BIG FRIKIN DISCLAIMER 1: This method won’t fix a poor-quality blade or one that was initially ruined during forging or heat-treat.

BIG FRIKIN DISCLAIMER 2: If you do this wrong you can easily ruin the blade!

Rejoice Greatly!

But what parasitic-worm-induced brain fever made your silly deranged servant suggest that Woody should rejoice when the cutting edge of his new chisel crumbles? I assure you, my reasoning is sound, I have Woody’s best interests at heart, and I will explain all to him when he sobers up. Probably tomorrow afternoon, at this rate. (ツ)

But I’ll explain it now to you, Beloved Customer, if you will be good enough to get me a root beer to wet my whistle from Woody’s cooler over there. No, that’s not a Class M-3 Model B-9 General Utility Non-Theorizing Environmental Control Robot, it’s a mini-fridge with a glass candy bowl epoxied to its top supported by a shop vac perched on two skateboards and wrapped in miniature blinking Christmas lights. Woody puts it out on his front porch for Halloween to thrill the kids. And its no coincidence it’s a good place to stash some cold adult beverages, and root beer too of course, close at hand. He’s very practical that way. Oh, BTW, please don’t tell SWMBO about the adult beverages, or you’ll ruin a great Halloween tradition and preclude many erudite discussions in the future: Vino Veritas

Ahh, that’s better. Nothing like an ice-cold root beer.

Now where was I? Oh yes, the reason for my optimism: A high-quality blade that crumbles like Woody’s did when brand new, and mellows after a few sharpenings, is highly likely to be an exceptionally fine tool!

On the other hand, a blade that is too soft when new will never crumble or chip, but it will always quickly dull and never improve. A veritable gasket scraper. (个_个)

There are exceptions, of course: some hand-forged blades are defective and crumbly from beginning to end, usually a result of overheating the steel during the forging process (called “burning” the steel), a rookie mistake. You should return such a defective blade to the retailer you purchased it from. If, however, to save a few bucks, you rolled the dice and bought a tool without a warranty, or purchased it from an online auction, to obtain satisfaction you will need to enlist the services of Murphy’s two bubbly buddies at the law firm of Doodly & Squat. Good luck with that!

Somehow I doubt Woody will thank me for solving this piece of the Mystery of Steel for him, but I am confident he will love the flavor of that chisel for the rest of his life.

YMHOS

PS: If you found this interesting, you may find other posts regarding the Mystery of Steel found in our “Sharpening Series” interesting too. The one at this link in particular is relevant to this discussion.

A kakuuchi oiirenomi chisel by Hidari no Ichihiro. The blade has been polished removing the black oxide formed in the forge. Beautiful work like this is no longer available.

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 I gag on a hairball if I lie.

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The Story of a Few Steels

Professional-grade Tools

The Care and Feeding of the Wild Mortise Chisel – Part 1

Sukezane brand 9mm mortise chisel (mukomachinomi) side view

It is well with me only when I have a chisel in my hand

Michelangelo 1475-1564

This is the first in a series of articles about the Mortise Chisel, especially the Japanese version called the “mukomachi nomi.”

Also called the “Joiner’s Chisel” in Japan, this is a specialized chisel used by specialist craftsmen to cut precise, smallish mortise & tenon joints when making furniture, cabinetry and joinery. Carpenters don’t use it, and few in that august trade have even seen one.

In this article your humble servant will introduce a tiny bit of the terribly long history of the mortise and tenon joint, and give a description of this tool.

In future articles in this series of international intrigue we will consider how to evaluate, adjust and even how to use the Mortise Chisel in general and the Japanese Mortise Chisel in particular. We will also touch on bevel angles and blade hardness problems, what to look for in a good mortise chisel, and how to examine it with an eye to increasing its performance. This is something most users of chisels never consider, but it can make a big difference in the case of mortise chisels. Indeed, I daresay most Gentle Readers and even a few Beloved Customers will mutter the equivalent of “Bless us and splash us” when they read it.

Of course we must not neglect to discuss how to effectively correct irregularities in our mortise chisel that negatively impact performance, irregularities most people never notice.

After our Mortise Chisel is properly fettled (they almost always have some problems) we will take our racing chisel out for a few laps, but prior to that we will consider how to effectively use it. Too few receive proper training nowadays in chisel work, but here are C&S Tools we feel it our duty to help our Beloved Customers maximize their skills.

We will conclude this series by taking the “Old Master’s Test,” just to make sure both our Mortise Chisel and our skills are improving.

While focused on the Japanese Mortise Chisel, the principles and improvements discussed in this series of articles are applicable to any chisel used to cut mortises.

While all Gentle Readers with eyes to see, ears to hear, and hands that love wood are welcome to share this hard-earned knowledge, it is intended primarily for our Beloved Customers, especially those who use chisels professionally to keep body and soul in close proximity.

Some Background

Your humble servant drafted this series of posts years ago, and has shared bits of it with friends and Beloved Customers from time to time when requested, but the information has not always been well-received for a number of reasons.

There is an old Japanese saying, one which probably originated in China, written 「馬の耳に念仏」and pronounced “Uma no mimi ni nenbutsu,” which translates to “Prayers in a horse’s ear.” Why are Buddhist prayers relevant you ask? Good question. You see, some of the principles your humble servant will present in this series directly contradict doctrine profitably expounded by some of the Popes & Professors of Woodworking in the West, and may offend their disciples. But like vespers to a beast of burden, wisdom is wasted on the willfully, woefully ignorant (wow, that sounds almost like iambic pentameter!).

But our Beloved Customers are neither angels nor asses but shockingly intelligent mortal humans with whom your humble servant is convinced the time has come to share the gospel of the Mortise Chisel as it was taught to me by Masters who have since abandoned this impure world to sort boards in the big lumberyard in the sky.

This series of posts is equivalent to a graduate school course in chisels, something like “Mortise Chisels 701.” And just like a course in advanced differential equations, most Gentle Readers will never need it. But never let it be said that your humble servant didn’t do his best to improve both the skills and the tools of our Beloved Customers.

Some History of the Mortise & Tenon Joint

Mortise chisels are used for cutting rectangular holes in wood usually intended to receive matching tenons to form a structural connection called the “mortise and tenon joint” between pieces of wood.

No one knows how long humans have been using the mortise and tenon joint, but it’s a technique older than nails, although modern humans with their lithium battery-powered, made in China, landfill-bound, multicolored plastic and rubber screwdrivers may find it difficult to imagine.

So let’s begin the journey by briefly examining just two well-documented extant physical examples that may provide motivation for using this enduring joint.

The oldest known wooden structure is a neolithic well liner discovered near Leipzig Germany, constructed from oak timbers shaped by stone adze and joined at the corners with half-lap joints and pinned tusk-tenons at through-mortises. Tests indicate the trees these timbers were split from were felled between the years 5206 and 5098 BC, making the assembly at least 7200 years old.

Next, let’s look at a less soggy but more recent, more complicated and elegant example.

The oldest existing wooden building in the world is a Buddhist Temple named Horyuji located in Nara Japan. Originally constructed around 600 A.D. and rebuilt around 700 A.D. after a fire, this huge 1300 year-old temple and pagoda complex was reconstructed using hundreds of thousands of hand-cut mortise and tenon joints, testifying to the longevity of wooden structural systems and the value of this universal connection technique.

Horyuji  is far more than just a temple to Buddhism, it is a temple to woodworking. If you haven’t yet visited it, you’re truly missing something. 

I mention these two examples to illustrate the universality, strength, and durability of the mortise and tenon joint. Anyone serious about woodworking must master this most ancient and essential connection.

The mortise chisel is the best handtool for the job of cutting mortises less than 15mm in width. For wider mortises, well-fettled oiirenomi or atsunomi are more efficient.

Japanese Mortise Chisels

12mm mortise chisel (mukomachinomi) Face (top) View
12mm mortise chisel (mukomachinomi) Side View
View of ura (flat) of the same 12mm mortise chisel
12mm mortise chisel (mukomachinomi). Please notice the rectangular cross-section precise right angles, and straight, clean sides. This is the most precise of the Japanese chisels. The apparent tan-colored stains on the shoulder are not rust but easily-removed sharpening stone residue left by the professional sharpener who prepared the blade.

In the Japanese language mortise chisels are called “mukomachi nomi” (向待鑿), with “nomi” meaning “chisel.” Don’t ask me the origin of the rest of the word because I don’t have a clue, and have heard few plausible explanations. There is another post linked to here that contains more information about this chisel.

I will use the term mortise chisel in this article to refer to the mukomachi nomi.

For our Gentle Readers interested in the Japanese language, there are several combinations of Chinese characters used to write mukomachi, none of which make much sense or seem related in any way to either tools or woodworking. The most common characters used are “向待” with the first character meaning “there” or “direction,” and the second character meaning “wait.” Combined, they seem to mean “Waiting over there,” or something like that.

I assume the name was originally phonetic and somebody decided to use these kanji because their pronunciation matched the phonetic name. This sort of linguistic contortion is seen frequently in Japan, and has been a source of confusion for all and sundry for many centuries. I blame it on elitist Buddhist priests going back and forth between Japan and China over the centuries, but it is typical of the Japanese people in general and priests in particular to take a perverse pleasure in intentionally making and using terms others can’t figure out.

This confusing practice is not unique to bald priests. When I was an engineering student, I recall the professors insisting we never attempt to simplify or too clearly explain the technical jargon of the trade to non-professionals because it was essential to job security for them to never quite understand it.

If you are familiar with Japanese architecture, you have seen the wooden lattice work that defines it in doors, windows, dividers, shoji, fusuma, koshido, glass doors, ceilings, and even fences, all items made by “tategushi” or “joiners” in Japan. Each piece of any lattice needs two tenons and two matching mortises to stay in-place, so a single piece of traditional Japanese joinery may contain literally hundreds of small, highly precise mortises, indeed thousands in the more complicated pieces. The Japanese mortise chisel was developed specifically at the request of joiners for this type of work. Therefore, it is also known as the “Tategu Nomi” which translates to “joinery chisel.” Few carpenters use this chisel.

Nora Brand 6mm Mortise Chisel (Mukomachinomi) Side View. Although it appears to be a simple, unsophisticated tool, nothing could be further from the truth. Based on the Kiyotada pattern, this is an especially beautiful example to those with eyes to see.
Nora Brand 6mm Mortise Chisel (Mukomachinomi) Ura View
Nora Brand 6mm Mortise Chisel (Mukomachinomi) Shoulder View. Exceptional shaping and filework .

Japanese mortise chisels are similar to other Japanese chisels in having a laminated steel structure with a hollow-ground ura (flat), an integral tang, wooden handle, and steel ferrule and hoop. Unlike most other chisels it has a rectangular cross-section with sides usually oriented 90˚square to the hollow-ground ura, and either flat or just slightly hollow-ground to better keep the blade aligned in the cut and to dimension and smooth the mortise’s walls.

Western mortise chisels do not typically share this detail, although unusually intelligent and observant Western woodworkers of course modify their chisels to gain similar benefits.

If speed and precision are important to you, then the sides of the chisel being oriented at 90° to the ura absolutely provide a serious advantage when cutting most mortises because the sides, and especially the two sharpish corners where these three planes meet, will effectively shave and precisely dimension the mortise’s side walls as the mortise is being cut without the need to pare them later.

Unlike most mortise joints cut with oiirenomi or atsunomi, so long as the mortise is the same width as the mortise chisel, and the user has the ability to maintain the chisel at the right angle while striking it with a hammer, the width of mortises cut with this chisel are usually quite precise and seldom if ever need be cleaned with a paring chisel. This functionality means that you can cut mortises, and especially small ones, both precisely and quickly with great confidence. It’s not called the “joiner’s chisel” for nothing.

The mukomachi chisel does not work as well in wider widths because of the increased friction between the chisel’s sides and the mortise’s walls. For joints wider than 15mm, please use a trued oiirenomi or atsunomi. And don’t forget to use your oilpot.

Conclusion

In the next class in our graduate course on the care and feeding of the wild mortise chisel, we will examine the various details to look for in an effective mukomachi nomi, most of which are applicable to other chisels such as oiirenomi and atsunomi too, indeed any chisel intended to be used to cut mortises including Western mortise chisels.

But wait a minute! Before ya’ll run out of the classroom like a caravan of crazy stoats chasing a pixie, please pick up your homework assignments from the table by the exit doors. And please, don’t leave your empties behind on the floor. Paper coffee cups are one thing, but discarded aluminum beer cans attract out-of-work divorce lawyers and other slavering vermin.

See you next time.

YMHOS

Your most humble and obedient servant’s set of well-used mortise chisels. The 8 older pieces on the right are by Kiyotada (1.5mm~15mm). The two 2 newer chisels on the far left are by Nora. Over the years I have used these tools both professionally and as a hobbyist more than any other of my chisels, as you can perhaps tell from the differing blade and handle lengths which have become shorter with use. A stoic tool, they gossip among themselves less than most other chisels. They are good friends and reliable workmates that worked hard for many years to pay rent, tuition and to buy food for the wife and babies.

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 Mama Shishi bite my head off.

YMHOS

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The Mystery of the Scratched Blade

Redwoods

The wiser a man is, the more he stands ready to be educated.”

Joe Abercrombie, A Little Hatred

In this post your humble servant will offer some advice that, if followed, will save Gentle Readers time, money, and wear and tear on their valuable woodworking tools. These are not original techniques; I stole them long ago from professional woodworkers in Japan. Wise Gentle Readers will be as bold.

But first we must solve another mystery, so prepare to enlist the help of your inner Agatha Christy.

As with the other mysteries we have examined, this one involves no dark and foreboding alleys shrouded by ominous mist and concealing footpads with rubber knives, or bottles of vintage Tabasco Sauce spiked with arsenic. Indeed, nothing so mundane.

Investigating the Scene of the Crime

Last December your humble servant received an ordinary Christmas Card from an old friend, probably a “re-gift.” It was unusual in that it contained brick dust. The sender of the card was my old friend Woody, a charming fellow, diligent woodworker, amateur thespian, and possible alcoholic. Gentle Reader may recall this gentleman from a previous adventure I wrote about called The Mystery of the Brittle Blade. Wait a minute! Now that I think about it, you went with me to visit Woody at that time and actually helped solve his little mystery. Thanks for your help!

BTW, the screenplay for that story is currently being reviewed by top producers and directors in Hollywood, at least that’s what the movie promoter I met at Krispy Creme Donuts here in Tokyo promised (ツ). He seemed like a reliable guy so I paid for his donuts and coffee.

Obviously, Woody’s dusty Christmas Card was a subtle cry for help so I went to visit him in his rickety, leaning workshop during my international travels last January. When I got onto the airplane I was shocked to find myself only one of approximately sixty travelers on a commercial flight that normally carries 350+ passengers, so I reclined across the center aisle of seats in cattle-class and slept like Nero after a night on the town.

Gentle Reader may recall Woody’s shop from the visit we made there together. Yes, it’s, still cold and dark and filled with the pungent funk of his faithful mutt Stinky.

Upon entering his shop I found Woody collapsed on the floor, an empty tequila bottle in one hand and a shiny bronze No.4 smoothing plane by Lie-Nielson in the other blubbering like a fool and muttering something like “Death, a necessary end, will come when it will come.” Woody ain’t much of a scholar but he has a romantic soul that sees every difficulty in life as Shakespearean in nature.

Seeing that my friend would be of no help in solving this mystery, I left him on the floor to practice his lines while I began my investigation of what, judging from the source material he was reciting, could only have been caused by something akin to Brutus’s betrayal.

The obvious first clue was his No.4 smoother, so I pried it out of his paws, dried the tears he had dribbled all over it, and observed a series of deep, uneven scratches on its sole, more or less in line with its the long direction. Whereupon, I twirled my white mustaches like an older, more handsome Hercule Poroit, and asked myself the following questions:

Question 1: What could have possibly created these scratches? Had iron pixies been using Woody’s beautiful plane to shave bricks?

A quick investigation of the workshop revealed several suspect bricks, but no signs of iron pixies at play. I remembered seeing Woody use these same bricks to brace the legs of his combination router table and barbecue betimes (he makes wonderful barbecued pork ribs, marinated in a whiskey sauce, BTW). I concluded it unlikely that either Woody or pesky pixies would have used this valuable plane to shave bricks at the unthinkable risk of disturbing a delicate combination tool (router table/barbecue) of such importance.

As I considered the wood Woody had been working, another question popped out of my brain like an egg from a hen:

Question 2: Is there anything that grows naturally inside a tree that is harder than a handplane’s sole and large enough to have caused such deep scratches? And if they do exist, could these particles have been maliciously concealed inside the growing tree by compadres of the shambling horde of 6-armed, green-skinned, Fanta-guzzling aliens that follow me everywhere? BTW, If you have seen these aliens, please send photos!

I next removed the plane’s blade, which was made of a tough and difficult to sharpen metal called A2, developed for making dies and other industrial components, and checked its condition. As suspected, the edge was not just deadly dull, but exhibited dents perfectly in-line with the deepest scratches in the plane’s sole. Egads! The thlot pickens!

Of course, Gentle Reader is aware that many varieties of wood contain hard silica particles that can wear out tools and quickly dull cutters, but they are seldom large enough to create deep scratches of the kind I saw on Woody’s plane’s sole. Hmmm.

Question 3: If these hideously-hard particles did not grow inside the tree, and were not concealed inside the tree by aliens, exactly how did the infernal particles that made these scratches come into contact with Woody’s pretty plane?

To make a closer visual inspection possible, I recovered my magnifying glass and deerstalker hat from my truck parked in Woody’s beer can-cluttered driveway.

Could the damage have been caused by nails, screws or staples left in the wood? Perhaps, but the appearance of the damage to the blade would have been different.

Pixie toenail clippings? Happens more often than we realize.

A tiny fragment from a divorce lawyer’s heart? Certainly any piece of such an organ would be harder than stellite, but being a fragment of a microscopic organ, such particles are harder to find than an honest politician in Shat Francisco.

“No,” I confidently declared; The culprit was harder than all these substances, more insidious than even Murphy’s pointy purple pecker, a substance all around us, one we often ignore. Rejoice Woody, for the mystery is solved!

Dust & Grit

Logging Redwoods in Humbolt County California, 1905

Politics and journalism aside, we live in a dusty, dirty world, and although the steel in your tool blades is very hard, ordinary dust and dirt contain plenty of particles much harder. I guaran-frikin-tee you that collision with even a small particle of mineral grit embedded in the surface of a piece of wood can and will damage a blade’s cutting edge.

You may believe the damage is minimal and of little concern, but every time your blade becomes dull, you must resharpen it. Every sharpening session costs you time pushing the blade around on stones, time not spent cutting wood. And sharpening turns expensive blades and stones into mud. This is time and money lost forever.

And the abrasive action of dirt and grit embedded in wood is not hard on just chisel blades, plane blades and the soles of steel planes, but is even harder on sawteeth and wooden planes.

And the damage is not limited to just your handtools either. Take a closer look at the steel tables of your stationary equipment such as your jointer or tablesaw. Unless they are new, you will find scratches. Has that purple pervert Murphy been smokin dope and humpin sumpin on your jointer’s bed when you weren’t lookin?

Nay, Gentle Reader, supernatural causes aside, and unless you have been dismembering the bodies of divorce lawyers in your workshop, these scratches are clear evidence that the wood you’ve been working is neither as clean as it looks, nor as clean as it should be. You’ve gotta do something about that.

Ruba Dub Dub

So what can you do about damaging dust and grit? Strange as it may seem, the simplest and surest way to get rid of dirt and grit is to follow your mother’s instructions about cleaning the bathtub: Simply wash it with soap, water and a wire brush, followed by a rinse.

Bet you never thought of washing wood before have you?

The idea is to wet, scrub with a wire brush, and quickly rinse the dirt and grit off the wood, not to make the wood soaking wet, so none of that “rinse and repeat” nonsense, and don’t get carried away with the water hose. A bit of dishwashing soap or washing soda mixed in the water bucket will help lift out dirt and grit.

Don’t forget to pat each board down immediately afterwards with clean rags to remove surface water. Then separate each board, rest it on stickers on-edge out of direct sunlight, and allow time and circulating air to dry it.

Remember to wet both sides of each board to minimize warping. And don’t soak a lot of water into the ends.

Disclaimer: Rubba-dub-dub is not well suited for thin material or laminated wood products that might easily warp, or delaminate, or if you are in a hurry, or if you lack adequate space to properly air-dry the wood. 

Whether you wash the wood with water or not, be sure to do at least the following two steps on every board before you process it with your valuable tools.

Scrub Scrub Scrub

If you can’t wash the boards, use a steel wire brush to dry-scrub all the board’s faces both with and across the grain. Yes, I know it makes the surface rougher. Tough pixie toenails. Scrubbing with a stiff steel brush is extremely effective at removing dust, dirt, embedded particles of grit, and even small stones from long grain. Give it a try and you will both see and smell the dirt and particles expelled. Pretty nasty stuff sometimes.

Saw Saw Saw

Second, and this is supremely important, before planing a board either by hand or using powertools, saw 2~3mm off both ends. This is why you have that circular saw with the carbide-tipped blade. If you can’t do that, at least use a steel block plane, drawknife, or other tool to chamfer all eight corners of the board’s ends to remove both surface dirt and the worst of the embedded grit thereby saving your planes, planer and/or jointer blades from scratches.

This step is critical because grit and even small stones frequently become so deeply embedded in endgrain that even a steel brush can’t dig them out. But sure as God made little green apples, Murphy will place them directly in the path of your plane blade.

If you do these things, I promise your tools will thank you over many years with abundant chips, shiny shavings and cheerful little songs.

Well, until either Woody sobers up or we meet again, I have the honor to remain,

YMHOS

Yosemite Valley California, 1865

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