The Varieties of Japanese Chisels Part 8 – The Atsunomi (厚鑿)

“Along with the milk of my nurse I received the knack of handling chisel and hammer, with which I make my figures.”

Michelangelo

INTRODUCTION

In a previous post, we looked at various types of oiirenomi (bench chisels) and mortise chisels. In this post we will examine a type of tatakinomi called the “Atsunomi.”

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Comparison of 42mm Mentori Oiirenomi and 50mm Atsunomi, both by Kiyotada

DESCRIPTION

The ”Atsunomi, ” written 厚鑿, translates to “thick chisel.” This is the largest variety of tatakinomi and is almost identical in design to its petite oirenomi sisters. Being larger, heavier and stronger it is able to transmit and endure the impact forces of heavy hammer blows from sunup to sundown and cut a lot of wood. Indeed, I can remember times when the handles of the 24mm and 30mm Kiyotada atsunomi in the photographs on this page became seriously hot after long hours of heavy hammer blows.

The 24mm chisel in the photograph below was the first atsunomi I owned. All three of the Kiyotada atsunomi chisels shown herein have seen hard use with heavy hammers, but have held up well.

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24mm Atsunomi by Kiyotada (face) Japanese White Oak handle
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30mm Atsunomi by Kiyotada (face) Japanese Red Oak handle. Definitely a Tokyo chisel.
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30 mm Atsunomi – Kiyotada (ura)

If I can liken the bench chisel or oiirenomi to a 1/4″ cordless hand drill, then the atsunomi is a 9 amp 1/2″ corded drill (when combined with the right steel hammer). Serious business indeed.

APPLICATIONS

The atsunomi is ideal for heavy work such as timber framing and wasting large amounts of wood quickly. However, carpenters are not the only trade to use them. 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, greater durability, and cost-effectiveness.

Because of its greater size and weight, the atsunomi is not as nimble as the smaller varieties of tataki nomi and demand greater strength and skill of the user. But on the other hand, it is very stable in the cut and wastes wood with oodles of gravitas.

As with all tataki nomi, the handle is big enough to use with one hand, but not two. Atsunomi always have a mild steel katsura crown installed at the end of the handle to reinforce it and prevent it from splitting under hammer blows.

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30mm Atsunomi by Sukemaru (Shirogami No.1 Steel, Japanese White oak Handle)
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30mm Atsunomi by Sukemaru. Nicely made ura
30mm Atsunomi by Sukemaru. Notice the excellent steel lamination at the bevel and wrapped up the side. Notice also the sexy shoulders and strong neck; definitely a Niigata-style chisel.

Standard widths for atsunomi are: 12㎜, 15㎜, 18㎜, 21㎜, 24㎜, 30㎜, 36㎜, 42㎜, 48㎜.

There are several varieties of atsunomi, some with very wide blades and others with very long necks, but I will not go into that level of detail in this post.

In Part 9 of this saga of romance and derring-do, we will examine the Uchimaru Nomi.

YMHOS

If you have questions please use the contact form below.

The Varieties of Japanese Chisels Part 7 – The Nihon Mukomachi Nomi (二本向待鑿)

“You can complain because roses have thorns, or you can rejoice because thorns have roses.”

Tom Wilson

INTRODUCTION

This tool is a specialty mortise chisel with two blades for cutting twin mortises at the same time. It was developed specifically for cutting mortise joints in wooden stiles and rails for doors, shoji, cabinets and other joinery.

DESCRIPTION

The name is a variation of the name of the standard mortise chisel ” mukomachi nomi” in my previous post, and no, I still don’t know what it has to do with ” waiting over there.” In front of this is added ”nihon” (二本) with ” ni” meaning ”2” and ” hon” being a counter for longish things, like pencils or trees, or in this case, blades. The word is pronounced ” knee hone.”

Interestingly, double or twin tenons are not called ” nihon hozo” (hozo means ” tenon”) but “ nimai hozo “ (二枚ほぞ) with “ni “ meaning 2. In this case the number is combined with the counter “mai “ used to count flat things like a sheet of paper or tenons. Japanese is almost as messy as English… I blame those pesky Buddhist priests for the complications involved in reading and writing Japanese, but I’m not sure who to blame for English.

Allow me to wander off the path a bit and talk about the Japanese language since you might find a few details interesting. If you don’t feel international today, please feel free to jump over the next few paragraphs.

The nation of Japan is called “Nihon” or “Nippon “ in the Japanese language and is written with the two characters “Ni “ 日  and ”Hon” 本 sometimes pronounced “pon.” Yes, the same pronunciation and one of the same characters used in nihon mukomachi nomi. Besides being a counter for pencils and trees and longish things, it also means ” book” and ” source. ” The word for the nation of Japan means “The source of the sun,” a jab by the Japanese at an arrogant Chinese emporer some millenia ago.

Spoken Japanese is not that difficult for English speakers to figure out, but the reading and writing are crazy difficult because of the vast quantity of Kanji, the multiple pronunciations possible for most of them, and the multiple meanings attached to many.

Elementary children are required to learn 1,006 kanji characters along with the various meanings and pronunciations. In total, a minimum of 4,272 characters are used in newspapers and magazines and must be learned before graduating middle school. Most educated people in Japan can read well over 6,000 of the over 13,000 registered kanji in Japan. Universal literacy requires a lot of study and memorization at a young age. This should give you an idea why education is so highly valued in Japan.

When I was a young missionary in Japan in the 1970’s, I spent several months stationed to Ehime prefecture in rural areas of the island of Shikoku, back when many farmhouses in that locale still had thatched roofs, no glass windows, and no electricty. Many of the older residents had spent their entire lives on their little farms and could not read or write, and had never seen a brown-haired blue-eyed foreigner before.

But the children in these mountain villages were always excited to see a foreigner and would swarm around and ask us where we were from. My standard response to this somewhat rude but innocent question was to point down at each of my legs and count them saying ”One leg, two legs. I’m a Nihonjin.”  The “nihon” I was was jokingly referring to was the same as the mortise chisel which is the subject of this post, not Japanese Nationality which is pronounced identically.

Now you know a stupid pun in Japanese, so never say you didn’t get your money’s worth at this blog!

The twin-blade mortise chisel is exceptionally difficult to make, and even new ones require the owner to perform a significant amount of tuning to convince them to perform well. They have never been common, and I am not aware of anyone forging them now.

APPLICATIONS

The twin tenons this chisel specializes in cutting are almost twice as strong as a larger single tenon, and are the preferred joint for high-stress wooden connections worldwide, especially joints in doors and windows. If you haven’t tried them before, you should. They look pretty cool as through tenons too.

Twin tenons have three advantages that justify the extra work. First, while they may have the same or even less cross-sectional area, they have more surface area than a single tenon in the same space, creating greater friction when assembled, if properly cut, creating a joint that is much more likely to stay assembled when stressed.

Second, this larger surface area also means a larger glue area, a big advantage with the right glue.

And finally, twin tenons are much more resistant to twisting, an huge advantage for highly stressed joints in operable doors and windows. This is their biggest advantage and is nothing to sneeze at. If you want a door to last, always use twin tenons, at least at the bottom rail.

Sokozarai chisel used to clean and shave the bottom of mortises

I purchased one of these chisels many years ago. They are difficult to tune. But even after all that work, the gentleman I learned tategu work from many years ago was not impressed with my clever tool insisting that a regular mortise chisel does a better job. There is an obscure structural reason why this makes sense, which I will not delve into here, but I did not ask Mr. Honda at the time for an explanation because it would have been improper to question a master who had been a professional joiner at his level for 60 years.

I can’t get these chisels made anymore, and know of no blacksmith that makes them nowadays. The time is not far away when handmade tools will not be available except as collectors items.

YMHOS

The Varieties of Japanese Chisels Part 6 – The Mortise Chisel (Mukomachi Nomi 向待鑿)

The best carpenters make the fewest chips.

~English proverb, c.1500s

INTRODUCTION

Japanese mortise chisels are called “Mukomachi Nomi” 向待鑿. I am unsure of the origin of the name, but the Chinese characters can be read as meaning “wait over there.” A curious name, it may refer to the shape of the transition from blade to neck, called a “machi” which is unique in Japanese chisels. I will simply call them “mortise chisels.”

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12mm Mortise Chisel – Sukezane (Side View)
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12mm Mortise Chisel – Sukezane (Ura View)

DESCRIPTION

Mortise chisels are single-purpose tools for cutting rectangular holes in wood for mortise and tenon joints, the oldest recorded wood joint known.

Unlike other Japanese chisels, and even Western mortise chisels, the sides of the Japanese mortise chisel are shaped square to the “flat” instead of being angled slightly less than 90 degrees. The surfaces of the sides are of course straight along their length, but are either flat or slightly hollow across their width.

Other varieties of chisels have sides angled inwards to prevent the chisel from binding in the cut. This is less than ideal, however, when cutting small mortises because it allows the chisel to twist inside the mortise scoring the sides and reducing precision. The Japanese philosophy is that the blade’s sides should shave and clean the mortise at the same time it is cutting it so the sides don’t require additional cleanup with a paring chisel. Its a matter of precision and efficiency.

The straight flat sides of the mortise chisel have a relatively larger surface area that can create a lot of friction in the cut making extraction difficult in some cases, so the standard maximum width is 15mm.

Many advocate using double bevel cutting edges for Western mortise chisels. I have no problem with double bevels for atsunomi used to cut wide, deep mortises because the double bevel tends to kick more waste out of the mortise hole than a single flat bevel, although double bevels are more trouble to sharpen. But in the case of the standard Japanese mortise chisel, I recommend using a simple flat bevel for two reasons:

The first reason is that, since sharpness is critical for precise work, and a flat bevel is quicker and easier to sharpen, a flat bevel is more precise.

The second reason is that a flat bevel tends to stabilize the chisel in the cut more than a double bevel blade can, keeping it from twisting out of alignment and gouging the sides.

The lubrication provide by an oilpot makes using a mortise chisel quicker and the final product cleaner and more precise. Please see my previous post on the subject. https://covingtonsons.home.blog/2019/05/09/the-essential-oilpot/

APPLICATIONS

The mortise chisel is a specialist chisel for joinery, cabinetmaking and furniture work. It is not generally used by carpenters. Craftsmen that routinely use mortise chisels work to much tighter tolerances than most woodworkers, so a professional-grade mortise chisel must be forged and shaped to tighter tolerances than other chisels.

I only have one blacksmith with the skills and attention to detail required to make mortise chisels to my specifications. He thinks I’m too picky. I think he’s too stubborn. We’re like an old married couple(ツ).

If you need to cut lots of precise mortise holes quickly, then this tool will definitely improve your results and increase your satisfaction. It may not be the most handsome chisel in your toolchest, but you will come to rely on it more than any other for quality joinery work.

Standard widths for mortise chisels are 3mm, 4.5mm, 6mm, 7.5mm, 9mm, 12mm, and 15mm, but Sukezane won’t make 15mm mortise chisels for me anymore, dagnabit.

More than any other, mortise chisels are subtle, intelligent beasties, or at least they can be. I will talk more about what to look for in a good mortise chisel, as well as how to realize their Einstein-like focus to help you do better work, in future posts.

If you have questions, please use the form below to make contact.

YMHOS

The Varieties of Japanese Chisels Part 5 – High-Speed Steel Oiirenomi (HSS 追入鑿)

“Life is not a matter of holding good cards, but of playing a poor hand well.” – Robert Louis Stevenson

INTRODUCTION

So, you finished building that fine cabinet, or 8-panel entry door, or carved balustrade and the day has come to install it at the jobsite. Will you need to cut a bit of gypboard or lath-and-plaster while installing it? Might your chisel get jammed against or into bricks or concrete in the process? Will you need to cut a notch in sandpaper-grit filled plywood or OSB? Any hidden screws or nails in the way that might require more than stern words?

Jobsite installations and remodeling often demand nasty work everyday tools can’t accomplish without serious damage. At that moment, having a tool tougher than the job is the difference between working and whining. This is that tool.

DESCRIPTION

HSS oiirenomi are a modern variation of mentori oiirenomi made using high-alloy steels tougher and more resistant to abrasion and high temperatures than more traditional steels.

Sukemaru High-speed Steel Oiirenomi

These chisels are useful for doing remodeling work and cabinet and equipment installations where plywood, MDF, OSB, LVL, drywall, acoustic board, insulated board, plaster, mortar, underlayment and studs full of hidden nails, and even ALC (autoclaved lightweight concrete) panels need to be cut, trimmed, fitted or demolished. Demolition…Oh joy (not).

Although High Speed Steel (HSS) won’t become as sharp as plain high-carbon steel, and takes more time to sharpen using a grinder and diamond plates, when you need to cut or trim the hard abrasive materials listed above, these blades will keep clippin’ without chippin’ when a standard chisel would be turned into an expensive gasket scraper. Also, one can quickly repair the damaged edge on an HSS chisel with a bench grinder or angle head grinder of the sort found on any construction jobsite without burning or softening the steel, a handy feature indeed.

HSS oiirenomi are hardened using special processes that leave the metal bright instead of creating the black oxide skin typical of standard high-carbon steel blades, an appearance some people find attractive.

Before I tried my first HSS oiirenomi, I kept a couple of old plastic-handled steel-cap Stanley chisels in my toolkit as “beaters” for cutting gritty, abrasive materials. They were soft and instantly dulled, but their edges would dent instead of chipping and were easily repaired. Poor things; some days they ended up looking more like rounded-over wide-blade screwdrivers than wood chisels. HSS chisels are just the ticket for this kind of brutal work.

The chisel pictured above was manufactured by Mr. Usui Yoshio under his brand “Sukemaru” (助丸). He is the fourth generation in this long line of famous blacksmiths.

The blade is one-piece of high-speed steel, not laminated high-carbon steel. The neck, however, is a softer, more malleable stainless steel which adds toughness to the tool while reducing costs.

Interestingly, the blade and neck are not welded together, but are connected by spinning the neck at high speed and forcing it against the stationary blade fusing the two components together more securely than is possible by welding. An amazing sight to see. High-level mechanical engineering going on here, boys and germs.

Standard widths for high-speed steel oiirenomi are 3mm, 6mm, 9mm, 12mm, 15mm, 18mm, 21mm, 24mm, 30mm, 36mm, and 42mm.

If you have questions, please use the form below.

YMHOS


The Varieties of Japanese Chisels Part 4 – Kakuuchi Oiirenomi (角打追入鑿)

“Do not wait; the time will never be “just right.” Start where you stand, and work with whatever tools you may have at your command, and better tools will be found as you go along.”

George Herbert

INTRODUCTION

The oldest style of oiirenomi currently available nowadays is called ” kakuuchi oiirenomi” (角打追い入れ鑿)which means ”square-forged oiirenomi,” refering to the squarish shape. In cross section, the blade is rectangular with 4 more-or-less square outside corners. Other than this cross-sectional detail, it is identical in appearance to the mentori oiirenomi we discussed in my earlier post. https://wordpress.com/block-editor/post/covingtonsons.home.blog/297

Kakuuchi Oiirenomi – Hidari no Ichihiro (Hyotan mark)
Kakuuchi Oiirenomi – Hidari no Ichihiro (Polished; Hyotan mark)
Kakuuchi Oiirenomi – Hidari no Ichihiro (Hyotan and “Mi” marks)

DESCRIPTION

Where the Shinogi Oiirenomi in the previous post is thin and light, the Kakuuchi Oiirenomi is more bulky and heavy. They are also stiffer in the blade and even in the neck, which can be an advantage in narrower widths.

This added stiffness is not due to the extra mass of metal alone, but also to the fact that the steel layer is wrapped further up the blade’s sides than is possible for the thinner beveled sides of the mentori oiirenomi, as you can see in the photos above. Wrapping the high-carbon steel cutting layer up the blade’s softer low-carbon steel sides in this way creates in effect a hardened steel “U” channel with an increased moment of inertia, which makes the blade much stiffer. The thicker the chisel’s sides, the deeper the U channel, and the stiffer the blade.

The U-channel construction of Japanese chisels is a clever but subtle structural detail unique in the universe of chisels and one most people are not aware of.

Carving chisels do not have this U-channel detail and therefore are not as stiff or as tough as chisels that do. When you are considering buying a chisel, this is an important feature to confirm.

Kakuuchi chisels take less time for a blacksmith to shape than the mentori oiirenomi we discussed in Part 2 of this series. The difference in shaping these two styles of chisels is the added step of grinding the extra bevels that make the mentori oiirenomi sleeker.

Indeed, most styles of Japanese chisels can be obtained with a Kakuuchi cross section, including the oiirenomi version shown in this post, as well as atsunomi and usunomi, chisels we will examine in future posts.

Kakuuchi-style chisels take a little more effort to sharpen because the area of the bevel is larger, and more significantly, the area of the hard steel layer is greater, but on the other hand, they feel more stable on the stones.

More than a preference for greater weight, stiffness and stability, I suspect most individuals who prefer this old-fashioned chisel are making a fashion statement, something like “brogues not oxfords,” if I can adapt a movie quote.

In my opinion, they are not as elegant in appearance as either the mentori oiirenomi or shinogi oiirenomi referenced in previous posts, but they do have undeniable dignity and presence.

What do you think?

Image result for 1956 ford truck

YMHOS

If you have questions, please use the form below.

The Varieties of Japanese Chisels Part 3 – The Shinogi Oiirenomi (鎬追入鑿)

“The best investment is in the tools of one’s own trade.”

Benjamin Franklin

The next variety of oirenomi we will look at is called the ”shinogi oiirenomi” (鎬追入鑿).

Hidari no Ichihihiro Shinogi Oiirenomi Blade
Shinogi Oiirenomi – Nagamitsu 長光

Shinogi (鎬) means ”ridge” as in the angled ridge of a rooftop or mountain. It is pronounced “she-noh-gee.” I believe the word was borrowed from the sword world where it refers to an angled ridge design on the back edge of Japanese swords (shinogizukuri 鎬造り). This detail is used not only in tatakinomi but in tsukinomi as well.

鎬が高い図
Two Angles of Sword Shinogi
日本刀の断面図
Blade Cross-section
View of Sword’s Shinogi and Hamon

Shinogi oiirenomi are beveled like mentori oiirenomi but are different in that the bevels extend all the way to the centerline of the blade’s face creating a definite ridge. The thickness of the blade’s right and left edges is typically thinner than oiirenomi making it easier to get into tight corners.

I am very fond of this handy, lightweight style of oirenomi and keep a 10pc set mounted to the inside of my toolchest’s lid.

The downside to this design is that the chisel blade loses some stiffness compared to other styles, so they are less than ideal for heavy-duty wood hogging.

Some call these ” umeki” or ” dovetail” chisels. Indeed, some blacksmiths will grind the bevels to a very thin edge for this purpose.

My blacksmiths will not create these thin edges for three reasons: First, shinogi oirenomi are not all that rigid to being with, and thinning the sides further is inviting breakage. Second, warpage is especially difficult to control in thin cross-sections resulting in more rejects and increased costs. And third, people always cut themselves badly using chisels with sides made thin enough to actually fit dovetails. Neither my blacksmiths nor I want that responsibility.

Most umeki chisels do not have the thin sides most people expect.

If you need very thin, sharp sides, you should grind and polish the bevels yourself. Don’t forget to keep a first-aid kit close by, one you can use with just one hand. Seriously.

Shinogi oiirenomi are available in the same widths as oiirenomi.

In the next post I will introduce an old-fashioned but still useful oiirenomi called the “kakuuchi oirenomi.” Stay tuned.

If you have questions or comments, please use the form below.

The Varieties of Japanese Chisels Part 2 – The Mentori Oiirenomi (面取追入鑿)

42mm Hidarino Ichihihiro Mentori Oirenomi

INTRODUCTION

The oiirenomi (pr0nounced Oh-ee-reh-no-me) is the most common variety of Japanese woodworking chisel, and the style best known both inside and outside Japan. There are several types of oiirenomi. In this post we will look at the most popular type of oirenomi called the ”mentori oirenomi” ( 面取り追入鑿) meaning ” beveled” oirenomi.

DESCRIPTION

As mentioned in my previous post in this series, nomi means ” chisel, ” but the term ”oiire” 追入れ” is not so straightforward. It is composed of two Chinese characters: ”Oi” 追いmeaning ”to chase” or ” to follow,” and ”ire” 入れ meaning ” insert” or ”place in.” I am uncertain of the origin of this word, but some hints of the original meaning may perhaps be deduced from the characters.

As the name suggests, this chisel’s face is beveled at both sides making it lighter and better able to get into tight locations than the older-style kakuuchi, which we will examine in a future post.

I think most people agree that the two bevels moving up the blade, curving around the shoulder, and feathering into the neck give this chisel a sculptural, elegant appearance. The bevels do sacrifice some stiffness and authority compared to the kakuuchi style, but clearly, these compromises are acceptable to most consumers.

APPLICATIONS

A member of the tatakinomi family, it is designed to be struck with a steel hammer and has a katsura crown on the handle’s end to prevent splitting.

There are larger types of tatakinomi called atsunomi better suited than the oiirenomi to heavy cutting and wasting wood in applications such as timber frame joints, and most of those share the same mentori bevel detail, but oiirenomi are better suited to lighter tasks such as furniture work and interior installation work the same as Western bench or butt chisels.

Oiirenomi in general and mentori oiirenomi especially are light-weight, relatively inexpensive, and handy to use. All woodworkers in Japan own at least a few of these. They are sold separately but 10 piece sets are the most common arrangement.

If you have any questions about this post or our products, please contact us using the form below:


The Varieties of Japanese Chisels Part 1 – The Main Categories

“Electrical tools are consumables; our tools are part of our bodies. Do not treat tools as just things. It is a mistake to think of tools as just your own. The shape of every tool was not decided recently. Over a long, long time it was decided that this form would be most useful.”

Nishioka Tsunekazu, Temple Carpenter in charge of the Horyuji and Yakshushiji Temple Restorations
Ichimatsu Tsukinomi – Kiyotada

Introduction

There are many varieties of Japanese chisels, and most people, including Japanese, are confused by the meanings of their names, and their various applications. I am not an historian or archaeologist, but I have been using them for over 40 years both professionally and for the fun of it and like to flatter myself I know a bit about them. Perhaps this and future posts will help de-muddle a little of the confusion.

In this first post in the series I will explain the components of Japanese woodworking chisels, and the two main categories. In later posts I will explain the various types of chisels included in these categories in some detail.

But let’s begin with some language matters.

Terminology and Translation

Where a suitable English word is available, I will use them, but for the most part, I will employ the Japanese terms converted from Kanji (Chinese pictogram characters) and Hiragana (phonetic Japanese characters) to the Roman letters used in most English-speaking nations.

The word for “chisel” in Japanese is “nomi” (鑿). The Chinese character used to write this word is complicated, so it is normally converted to the phonetic hiragana letters as “のみ.” You will notice that nomi is part of every chisel’s name, so I will use it too.

Structure and Components of Japanese Chisels

The design of Japanese chisels is a little more complicated than their Western counterparts, but the basic components are generally the same. So let us examine the similarities and differences.

Blade and Neck Construction

42mm Hidarino Ichihiro Oirenomi – Face View

Traditional Japanese chisels have laminated blades with a body, neck and tang made of iron or very low-carbon steel that remains relatively soft during heat treatment. A layer of high-carbon steel is laminated to this iron body at the blade to form the cutting edge. During the quenching process, this layer becomes very hard, typically 62~67 Rc versus the typical hardness of 58~60 Rc found in Western chisels. The two layers are most visible at the bevel. This additional hardness has both advantages and disadvantages, depending on the crystalline structure of the steel after heat-treating and the skill with which the tool is used and maintained.

In the case of hand-forged (teuchi 手打) blades, this lamination is made by forge- welding the two types of metal over several heats using hammer, tongs, and anvil.

European chisels were also fabricated using this technique before the advent of mass-produced inexpensive steel. Unfortunately, this once-universal excellent technique has been all but forgotten outside of Japan.

Materials & Process

The best professional-grade chisels are made of high-quality iron and the purest plain high-carbon steel. These ancient metals are difficult to work, being very sensitive to temperature and thermal shock and tending to warp and crack badly in less than experienced hands. Many alloys and processes have been developed over the last 60 years to make tool production more profitable using unskilled labor, but for simple cutting ability and ease of sharpening, nothing rivals this combination.

The blacksmithing process involves forge-welding the two types of metal to form a laminated blade, then shaping and hand-forging over multiple heats, followed by carbon soaking and annealing, a coating of secret mud sauce after which the blade is heated to just the right temparature and subject to multiple quenches followed by multiple temperings. The process varies from blacksmith to blacksmith with each craftsman using different formulas and procedures. Of course, warpage must be compensated for by shaping a curve in the blade that straightens out during heat treatment. Learning these skills takes years of hands-on training from a young age under the eye of a master, and decades of dedication to quality. It certainly cannot be accomplished in a mass-production situation, much less by Chinese peasants or even CNC robots.

Mass-produced consumer-grade Japanese chisel are made of pre-laminated strip steel manufactured in steel mills by either cold-rolling or hot-rolling a layer of high-carbon steel to a layer of mild-steel. This material, called ” rikizai” (利器材)or ” fukugozai” (複合材)was originally developed for mass-producing inexpensive kitchen knives as a labour-saving material to reduce manufacturing costs.

Blades made from rikizai typically perform adequately for most consumers, but many professionals seek the higher performance of so-called ” fine-grain” steel’s smaller and more uniformly-distributed carbides found in hand-forged, expertly heat-treated blades. Those who develop the skills necessary to discern the difference between such professional-grade and consumer-grade blades, can never be satisfied with the inferior tool.

Hollow-Grind

42mm Hidarino Ichihiro Oirenomi – Back View

Japanese chisel blades have a hollow-ground back (the so-called ” flat” on Western chisels) which makes the harder steel easier to sharpen and keep flat. Without this hollow-ground ura feature you would find sharpening a chisel blade of similar hardness time consuming and almost impossible to keep flat over many sharpenings.

Tang and Ferrule

Japanese chisels appears at first glance to be socket chisels, but they are definitely tang chisels. The handle incorporates a steel ferrule shaped like a truncated cone and called the “ kuchigane” (口金) which translates to “mouth metal.”

The Four Components of a Tatakinomi: Blade, Handle, Kuchigane, Crown

This component receives the reaction forces of hammer impacts from the blade’s shoulders converting these thrust forces acting in the handle’s long axis to compression forces acting on the handle’s end thereby preventing splitting and locking the tang tightly into the handle. It is a subtle but clever and effective design that combines the best features of both tang chisels and socket chisels without any of the downsides.

The Crown

The “Keima” Chess Piece

Chisels intended to be struck with a steel hammer have a sturdy steel hoop called a ” katsura” installed at the handle’s end to prevent the wood from splitting. The characters used for this word include 冠, pronounced “kan” or “ kanmuri” meaning “crown” or 桂 meaning Judas Tree or “ knight” (桂馬)as in the chess piece. The word Katsura can also mean “ wig” a term that does not quite work in this case because chisel handles are as bald as I am.

I have the bad habit of anthropomorphising my tools. They hate that, so to avoid giving further offence (they sometimes bite, donchano), I prefer to translate katsura as the more elegant word “crown” instead of the more constrictive word “hoop” or follically-challenged word “wig.”

Just in case you aren’t entirely confused, please note that this same steel hoop is also called a ”sagariwa” (下り輪) which translates to ”drop hoop, ” a term that is accurately descriptive because, over many years of hammer blows, the handle gradually shortens and the hoop “drops,” shifting its position down the handle.

The crown is made of relatively soft but still strong mild steel. In use, it may occasionally be struck by a steel hammer. This choice of material is not based on economics or convenience but on the practical reality that the face of a steel hammer impacting the edge of a hardened steel hoop would get dinged and even deform after enough hits.

But this creates another problem, namely that the crown may eventually become deformed by hammer strikes unless preventative measures are taken. This is not a trivial cosmetic matter because the hoop’s edge may deform to the point it curls back inside itself. Then, if the user continues to beat on the chisel, the hoop will gouge and eventually split the handle.

Damaged Crown and Handle

The best way to avoid this grief is to use a hammer with a flat instead of convex face and to properly setup the chisel when new. For instructions on doing this, please see my earlier post about Setting-up Japanese Chisels.

Another downside to the crown and steel hammer arrangement is that the end of Japanese tatakinoni are far from smooth and can be uncomfortable to use when paring. The solution to this is three-fold. First, setup the crown properly and chamfer and smooth its edges. Second, avoid hitting the crown with hammer so it doesn’t become rough and gnarly. And finally, use a tsukinomi chisel for paring. Life is good.

Handle Materials

Chisel handles can be made of a variety of woods, but strong hardwoods such as oak or boxwood are commonly fitted to chisels designed to be motivated with hammers.

Chisels not intended to be struck with a hammer can be fitted with more brittle but decorative wooden handles such as ebony or rosewood.

The Two Categories: Tatakinomi and Tsukinomi

Tsukinomi

There are two primary categories of Japanese chisels. I think these same categories apply to other traditions, but in the difference is especially clear-cut in Japan.

The first category is the “tsukinomi “ (突き鑿). Tsuki means “to push,” so tsukinomi refers to push, or paring, chisels. Standard widths range from 1.5mm to 48mm. Handle lengths and materials vary with the type of tsukinomi, the intended purpose, and personal preferences.

30mm Mitsuura Tsukinomi – Sukezane

Tsukinomi are pushed by hand and sometimes by shoulder in the case of the large ootsukinomi, known in the West as “slicks.” Most tsukinomi have relatively longer, more slender and elegant necks. They incorporate the same kuchigane ferrule at the blade end of the handle, but do not have a steel crown hoop reinforcing the opposite end.

Standard Ootsukinomi Set: 24mm and 48mm
Paring the Cheeks of a Beam Splice Using an Ootsukinomi
Paring a Rafter Post Seat Using an Ootsukinomi

By definition these chisels are not intended to ever be struck with a hammer. Even if the handle does not split, their more slender necks will not endure impact forces gracefully. More often than not they are used to clean and pare to final tolerances joints cut using other chisels.

Tatakinomi

The second main category of Japanese chisel is called the “tatakinomi” (叩き鑿)meaning “striking chisel.” This is the style of Japanese chisel best known outside Japan. These chisels are stronger and tougher than tsukinomi and are intended to be struck with a steel hammer.

42mm Atsunomi Ura – Sukemaru (300mm (11.8″) Overall Length)

Wooden mallets are not typically used with Japanese chisels. The logic for this practice is simple: A steel hammer is the smallest, lightest, and most energy-efficient way to motivate a chisel. The physics of this are self-evident. Accordingly, the logic behind the tatakinomi design is that, since it must efficiently remove lots of wood, and a steel hammer is the most efficient way to motivate a chisel, the tatakinomi’s handle must be designed and made strong enough to endure being struck by a steel hammer from sunrise to sunset. A simple calculus.

250 Monme Kosaburo Gennou (938gm, 330z) Black Persimmon Handle

By contrast, the Western tradition of using chisels with inherently fragile handles requiring users to obsessively baby them with relatively soft, energy-wasting, un-aerodynamic, big-ass mallets is illogical and inefficient. But to each his own.

Some people stubbornly insist on using mallets even to strike their Japanese tatakinomi. This reminds me of the country bumpkin that bought a newfangled chainsaw from a hardware store in town to cut firewood only to bring it back the next day complaining it was slower and more work than his old axe and handsaw. The puzzled hardware store owner checked the fuel and spark plug, but found no obvious problems. With a perplexed look he yanked the starter rope. The chainsaw’s motor started right up with a roar and a cloud of smoke. The shocked customer almost jumped out of his overalls in wide-eyed surprise, screeching “ what the hell’s that racket!?!”

According to the Takenaka Carpentry Tools Museum located in Kobe, there are 9 varieties of tatakinomi. https://www.dougukan.jp/tools/20

In Part 2 of this series I would like to describe some of these beginning with the “Mentori Oiirenomi.”

YMHOS

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The Essential Oilpot

If set up and maintained properly, the blades of quality chisels and planes will endure many decades of hard daily use. Maintenance is the hard part. This blog is about a tool that will not only make the chore of constant maintenance easier and more efficient, but will also make your other tools work better.

It is a sad truth that the blades of woodworking tools often receive more damage while they are waiting to be used than when they are actually being used.  Thankfully, corrosion of the sort that creates microscopic pits at the cutting edge can be easily avoided with common-sense solutions.

When not in use, store your chisels and planes where they will be protected from dust and large temperature swings. And oil your blades after every use to keep away oxygen, moisture, and chemicals that might make your expensive blades “turn red and go away.” I suggest you plan ahead to make it as easy as possible to apply good oil to your blades. An oilpot, or aburatsubo (油壺)as it is called in Japan, is a very useful, inexpensive, easily made, and time-proven tool for this purpose.

But oil pots are not just for the important job of keeping away corrosion. An oilpot close at hand will help to minimize the friction your chisels, saws, planes, and knives generate when cutting wood. The most striking benefit of this is that you won’t need to expend as much energy when working wood and your apparent strength and endurance will increase.  Perhaps more importantly, the wood being cut will be less able to deflect your tool’s blade away from the intended line of cut, increasing the precision of your work.

Besides chisels, planes and knives, the oilpot can be used to lubricate drill bits and augers.

You only need to look back in history a little way to see that these benefits are well established.

We know from the archaeological record that tallow, just rendered animal fat, was placed in grease pots and used as a tool lubricant in Europe from medieval times right up until petroleum products became widely available. It was also used in the Americas until the same time. Vegetable oil was used in Asia, and probably in Europe as well. I am told that the black crust found on many antique plane bodies (wood planes not aeroplanes) is oxidized and hardened tallow combined with dirt.

Indeed, I can recall my father, uncles, and grandfather using sticks of caning wax (a petroleum product) for the exact same purpose when I was a child, and before that my English ancestors probably used beeswax and tallow candle stubs. I haven’t tried soft tallow as a lubricant and probably never will since rancid fat has even less appeal to me than rancid vegetable oil, but the method I will describe in this post is a serious improvement over the ancient methods, in my opinion.

In Japan, an oilpot is made by cutting a joint of well-dried bamboo into a cup 3 to 4 inches deep. If you do not have bamboo where you live, a hollowed-out piece of close-grained barrel-making wood like White Oak, or a plastic mug, or even a segment of capped PVC pipe will work just as well. The important thing is the container not be made of metal, glass or ceramic or any other material approaching the hardness of a chisel blade.

Shape the cup so the bottom is very stable. Some people scallop the bottom so it essential rests on four or five spots at the perimeter. And a piece of sandpaper glued to the bottom will prevent your planes from dragging the oilpot around when pass their soles over the wick.

If you use bamboo or wood, prime and paint the inside of the cup, and underside of the foot, with a high-solids urethane or polyurethane paint. I used a natural urethane extracted from the cashew tree called “Cashew” on the bamboo joint in these photos. The gaudy orange color makes it easy to differentiate my oilpot from others on a jobsite

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Line the inside of the cup with an unbroken sheet of aluminum foil to prevent the oil from soaking through. The paint alone will slow down the oil’s movement through the wood’s fibers, but sure as hogs are made of bacon, without a reliable liner of some sort, it will eventually seep out making a mess.

Next you will need clean, white, cotton T-shirt fabric. Used clothing is fine. White because you want to be able to tell how dirty the fabric is at any time. T-shirt fabric because it sheds the least fibers. Clean because pixies hate it. If you don’t believe me, just ask them.

Roll it up very tightly, and bind it with string or thread. It will take several tries to judge just the right amount of fabric. You should be able to force this dense cloth wick tightly into the cup with  ¼” to ½” projecting above the lip. It must be a tight fit to prevent the wick from falling or pulling out accidently. Then, soak the cloth with your favorite lubricant and you’ll be ready to rock-n’-roll like Zeppelin. It will take some time for the oil to saturate the dense wick, so be patient.

In Japan, I was told to use vegetable oil and change the wick when it became rancid.  But I recommend you save yourself some trouble and at least one stinky wick and use a non-organic oil from the start.

Some people prefer straight mineral oil or scented furniture oil, which is just scented mineral oil. The lemony smell is nice. But carefully avoid any furniture polishes or oils that contain silicon because these will weaken glue bonds.

Some people prefer camellia oil, but be aware that the so-called camellia oil available commercially for rust protection is actually just mineral oil with a bit of yellow dye and some fragrance added, sold at ridiculously high price tag, much like commercial furniture oil. Caveat emptor, baby. But in truth, mineral oil is not only cheaper (sold as lubricant laxative in pharmacies), but performs better than genuine camellia oil because it will not become rancid and gummy.

While it sounds strange, the best lubricant in my experience is a lightweight, light-colored synthetic motor oil such as 5W Mobile 1. I have tried regular motor oil too, but the synthetic variety smells better, lasts longer and seems to perform better.

Store your oil pot in a metal or plastic container with a lid when not in use to prevent abrasive dirt from contaminating it. Some people make a container from a segment of PVC pipe with a flat end cap glued on to make the bottom and domed one left lose as a lid. Place some newspaper in the bottom of your container to absorb oil and stop the rattling noise.

Even a plastic bag will do until you find something better.

When you are cutting a mortise with your chisel, make it a habit to occasionally jab the cutting edge of your chisel into the oil pot, and even wipe the sides and ura (flat) on the wick to lubricate the blade. You will be pleasantly surprised to find that this bit of oil will make your chisel work not only go faster, but more precisely and with cleaner results. The oil will not weaken glue bonds.

Likewise, when using either a metal-bodied or wooden bodied plane, occasionally swipe its sole over the oil pot. This will greatly reduce friction and give you more control. But if you value your public dignity, be forewarned that the first few cuts after doing this will make you smile like a lunatic.

The same benefits of reduced friction and increased precision can be found in the case of handsaws too, although the difference may not be as noticeable.

Before you store your tools away for the day, a quick bit of oil from your ever-present oil pot will prevent rust and frustrate corrosive pixies.

During use, the cloth will naturally become frazzled and covered with sawdust and wood chips, and will discolor accordingly. No problemo.

If you drop the oilpot and it hits the ground, heaven forbid, Murphy’s Law of Buttered Toast dictates it will land oily-cloth down contaminating it with abrasive grit. If ignored, frikin Murphy will smugly use your oilpot to damage your tools and ruin your work. But never fear: If you simply brush the cloth vigorously with a steel-wire brush, sawdust, wood chips, dust and grit are easily removed.

Of course you always have a steel-wire brush close at hand to remove embedded grit from boards before planing them, right?

When necessary, you can re-roll or replace the cloth wick to expose a clean surface. As the cloth wears and stops projecting from the oilpot’s mouth, remove the wick and place some clean rags in the bottom to elevate it.

The oilpot is an ancient, dirt-cheap tool you will find to be a invaluable addition to your woodworking tool kit.

YMHOS

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Welcome to the C&S Tools Blog!

In this post I will introduce this blog’s purpose, my qualifications and motivations for writing it, and a description of the sort of subjects that will be posted.

It’s purpose is simply to share sound information regarding woodworking techniques, woodworking hand tools and construction work with an emphasis on Japanese hand tools and techniques

Although woodworking and construction are universal human activity, Japan has unique history and traditions and has developed techniques many find interesting. Indeed, most Japanese woodworking hand tools are different in some ways from their Western counterparts, and must be setup, maintained and used differently.

Unfortunately there is a lot of blather on the internet and even in print on these subjects that pound for pound is valuable as road apples and smells as sweet. I intend to provide a more professional viewpoint.

The content of this blog will not be a regurgitation by an amateur of things learned or plagiarized from books, magazines, YouTube videos, or heaven forfend, troll-infested woodworking forums, but will be based on real-world professional experience.

What relevant professional experience do I have, you ask?  To begin with, I worked as a joiner, cabinetmaker and carpenter for many years. I have worked in the construction industry most of my life as a contractor and direct employee of some of Japan’s largest general contractors. You could say I know the trade.

Much of what I know about woodworking and tools I learned directly from the professionals I worked with and tool makers whose opinions I sought out, most of whom have gone to the big woodpile in the sky. You could say I had good teachers.

I no longer use tools on the jobsite, but I am still involved in the Japanese construction industry. I have lived, studied and worked in Japan off and on for around 24 years since first coming here 43 years ago. You could say I know the neighborhood.

I have a masters degree in architecture and engineering from a prestigious Japanese university and am bilingual in both written and spoken English and Japanese languages, so you could say I know how to research and ask intelligent questions about technical subjects and understand the answers.

But what about the quality of the information? As in all things, you must judge the quality of the content for yourself. But here are a few things you should keep in mind when doing so.

We live in a confusing era of fake internet experts, absolutely corrupt journalistic standards, and blogs and publications authored by lazy opportunistic shills. Is this evaluation too harsh? I don’t think so. But whether opinion or scientific research results, a wise man will consider the writer’s motivations which inevitably skew the focus, quality, and sometimes even the veracity of information he presents.

I think there are three common and not mutually exclusive motivations for people to write blogs. One is a desire to share useful, interesting information. I like to think this is my motivation.

Another motivation is a desire to be popular and make money in the process. For these fellows, success is partly measured by the number of “clicks,” “likes,” and subscribers they get, and of course the acreage of banners and adverts on their webpage. Both their self-worth and income relies on infrastructure controlled by monstrously unethical companies like Google, Facebook, Instagram, Twitter, YouTube and Patreon, and the funding of viewers and sponsors. I pity them.

I have no problem with people touting a product or service or belief. Who knows, the information may be useful, so long as it doesn’t include too many lies or exaggerations and the touter is honest about his relationship with the item or service, as I am with my products. Sadly, too many bloggers, YouTubers, and politicians don’t reveal sponsor contributions in cash or goods but pretend their opinions and reviews are unbiased. Such behavior is indisputably unethical. I think a famous French soldier expressed my thoughts about such dishonest people well when he said: “I don’t want to talk to you no more, you empty-headed animal-food-trough wiper! I fart in your general direction! Your mother was a hamster, and your father smelt of elderberries!”

I will never accept sponsorships, contributions, banners, or freebies. I have no SEO goals. Those who want to read the things I have to share must find this blog without guidance from the Silicon Valley decepticons.

Perhaps the third blogger motivation is a disease called “writer’s dysentery.” This horrific affliction makes the victim feel sick in their guts unless they write and post something, anything, everyday regardless of relevance or quality. Many scribbler-types suffer from this frightful disease and practically gush like a trash pump. Thankfully, I am not infected with this malodorous malady. I spend too many hours every working day writing necessary documents for my company and clients and the construction projects I run, so I feel no compulsion to spend my free time writing for free.

Therefore, I will not subject you, Gentle Reader, to diarrhetic descriptions of my vacation, hobbies, boat, motorcycle, kids, grandkids, pets, my grandkid’s pets, or rambling step-by-step descriptions of landfill-ready woodworking projects imitating those eternally recycled in woodworking periodicals, subjects which make up 80% of the content of most blogs.

Now that it’s clear what I won’t write about, let’s look at what I will.

The craftsmen that make and use the tools that are a major subject of this blog are located far from most English-speaking readers, both culturally and as the crow flies. Communication with these people on technical subjects can be challenging. During my years in Japan I have built relationships with these craftsmen and learned much from them. I will share that knowledge in this blog.

I also plan to post interviews with Japanese craftsmen along with photos of their smithies, workshops, and jobsites as time and opportunity permit. Perhaps we can even do a few Q&A sessions with them. Please let me know what interests you in the comments below.

As a construction-industry professional in Japan, I routinely evaluate and hire Japan’s top general contractors and subcontractors for my Client’s projects. I will share some of those stories too (non-disclosure agreements permitting).

Some of the how-to subjects I intend to discuss will include tool setup, sharpening, maintenance and proper usage, as well as how to make some tools. And of course, woodworking techniques.

Regarding the frequency of posts, I am a busy man and dislike wasting time with pointless drivel. I will post only what I think is worthwhile, measured by my standards and your requests, when I can. And I will make no schedule commitments.

The one thing I do promise is the content of this blog will be worth more than you pay for it. You won’t find a better deal anywhere at twice the price.

If you have relevant questions, please ask. If you have suggestions or corrections, I am willing to learn. But to those who would use the internet’s anonymity to morph into snapping orcs or bellowing trolls, I say Go back to the Shadow!

Wanted: Hair Stylist, Esthetician, Ear Manicurist and Tooth Sharpener. Must like caves.

All others I welcome with bunny hugs.

Stan

Do I Need a Shave?

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