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 five-part series about the Mortise Chisel, especially the Japanese version.

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

In this post we will briefly examine a tiny bit of the terribly long history of the mortise and tenon joint, and give a description of this specialized chisel.

In future posts we will look at how to evaluate, adjust and even how to use the Japanese Mortise Chisel. We will also touch on bevel angles and blade hardness problems.

In subsequent posts we will discuss 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 will mutter something like “Splish us and splash us” when they read it.

Of course we will also discuss how to effectively correct irregularities in our mortise chisel that negatively impact performance, irregularities most people never notice.

After it is fixed (they almost always have problems) we will take our racing chisel out for a few laps, but prior to that we will consider how to effectively use this specialized tool. Too few receive proper training nowadays in chisel work, but here are C&S Tools we feel it our duty to help our Beloved Customer’s improve 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 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 Beloved Customers from time to time when requested, but the information has not always been well-received for a number of reasons.

There is a relevant Japanese saying written 「馬の耳に念仏」 and pronounced “Uma no mimi ni nenbutsu,” which translates to “Prayers in a horse’s ear.” You see, some of the principles I will present in this series directly contradict doctrine taught by some of the woodworking Gurus in the West. Life is too short to waste wisdom on the willfully ignorant when there are other, more basic subjects to address. But because Beloved Customers are neither horses nor asses but shockingly intelligent humans, your humble servant is convinced the time has come to expound the gospel of the mortise chisel. Perhaps it will be canonized some day (ツ)

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 C&S Tool’s Beloved Customers.

Some History of the Mortise & Tenon Joint

Mortise chisels are used for cutting rectangular holes in wood usually intended to accept 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 has certainly been longer than nails, and many thousands of years longer than screws, although modern humans may find it difficult to imagine. So let’s begin the journey by 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 the 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, 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 constructed using hundreds of thousands of 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 have not yet visited it, I urge you to do so. 

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, oiirenomi or atsunomi are more efficient.

Japanese Mortise Chisels

12mm mortise chisel (mukomachinomi) Face View
12mm mortise chisel (mukomachinomi) Side View
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.

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 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 is something seen frequently in Japan, and 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.

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 have literally hundreds of small, very 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
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 attentive 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 can 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.

In the next class in our graduate course in mortise chisels, we will examine the various details to look for in an effective mortise chisel. Most of these details are applicable in the case of other chisels such as oiirenomi and atsunomi too, indeed any chisel intended to be used to cut mortises including Western mortise chisels.

Before you run out of the classroom like a caravan of 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 aluminum beer cans attract out-of-work divorce lawyers and other such vermin.

See you next time.

YMHOS

Your most humble and obedient servant’s set of well-used Mortise Chisels. The 8 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 chisels both professionally and as a hobbyist more than any other, as you can perhaps tell from the blade and handle lengths which have become shorter with use. A stoic tool, they gossip among themselves less than most other chisels. Good friends and reliable workmates that helped pay the rent and feed the wife and babies for many years.

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YMHOS

The Story of a Few Steels

An illustration of the Eidai tatara furnace (a cross-section illustration is shown at the end of this article) with human-powered blowers to right and left. Looks like hot work.

The things that will destroy America are prosperity-at-any-price, peace-at-any-price, safety-first instead of duty-first, the love of soft living, and the get-rich-quick theory of life.

Theodore Roosevelt

The terms White Steel and Blue Steel frequently pop up in discussions about Japanese woodworking tools and kitchen knives. The usual misunderstandings abound in those discussions and BS takes majestic wing. In this article we will try to share some accurate information sourced directly from the steel manufacturer and our ancient blacksmiths that actually make and work these steels instead of the usual soft-handed shopkeepers and self-proclaimed experts living in their Mom’s basement.

We will begin by studying some etymology of two of Japan’s most famous tools steels. We will then drop into history class to discuss ancient domestic Japanese steel, and then shift our attention to why these modern steels came into being. After that, we will go to metallurgy class, but without the technical jargon, to explain what these steels contain and why. And finally, we will outline the defining performance characteristics of those same two steels in the case of woodworking tools.

Please ready your BS shovel.

Product Designations: Yellow, White & Blue Label Steels

These terms refer to tool steels manufactured by Hitachi Metals, Ltd. in their plant located in Yasugi City in Shimane Prefecture, Japan. If you are into woodworking tools or Japanese cutlery you have heard of these steels.

Hitachi, Ltd., founded in 1910, is one of Japan’s most prestigious manufacturers. Its subsidiary, Hitachi Metals, Ltd., was established in 1956 primarily through acquisitions.

“White Steel” is an abbreviated translation of HML’s nomenclature of “Shirogamiko” 白紙鋼, which directly translates to “White Paper Steel.” Likewise, “Blue Steel” is an abbreviation of “Blue Label Steel,” the translation of “Aogamiko” 青紙鋼.

Just as “Johnnie Walker Blue” is the commercial designation of a famous Scottish whiskey with a blue label pasted onto the bottle, Aogami is the designation of a high-carbon tool steel with a blue label pasted onto it. It’s that simple.

Since your humble servant can read and write Japanese, and the steel itself is neither white, nor blue, much less yellow, I feel foolish calling it White Steel or Blue Steel as many in English-speaking countries do, so prefer to call them Yellow Label Steel, White Label Steel or Blue Label Steel in English, or Kigami, Aogami, or Shirogami steel. Please excuse this affectation.

Now let’s go back in time a few hundred years. I promise to keep it concise.

Traditional Japanese Steel: Tamahagane

Tamahagane, written 玉鋼 in Chinese characters, which translates to “Jewel Steel” and is pronounced tah/mah/ha/gah/neh, is famous as the steel traditionally used to forge Japanese swords, but prior to the importation of steel from overseas, beginning with products from the Andrews Steel mill in England, it was once used for all steel production in Japan.

Before Admiral Perry’s black ships re-opened the many kingdoms and fiefdoms scattered across the islands that now comprise modern Japan, the only local source for natural iron was a material called Satetsu, a loose surface iron written 砂鉄 in Chinese characters, meaning ”sand iron,” and pronounced sah/teh/tsu. Satetsu looks exactly like black sand. It is quite common throughout the world, as you may discover if you drag a magnet through a sandy river.

Typically found in rivers and estuaries, for many centuries the area around Yasugi City in Shimane Prefecture was a prime source.

Satetsu was historically harvested in Japan using dredges and sluices creating horrendous environmental damage. Fortunately, the days of wholesale estuary destruction are in Japan’s past.

Although Aluminum is the most abundant metal on this rock we call home, iron is said to make up 34% of the earth’s mass. Japanese satetsu as harvested is a fairly pure form of iron lacking nearly all the impurities typically found in iron ore from mines.

Historically satetsu was refined in rather crude furnaces called ” tatara” to form clumps of brittle, excessively-high carbon steel.

A tatara furnace in operation. Satetsu is combined with charcoal and heated over several days. The resulting bloom steel, called “Tamahagane,” settles to the bottom in clumps and puddles and is removed by breaking the furnace apart.
出来上がった巨大な鉧を引き出します
The tamahagane that melted to the bottom of the tatara furnace being pulled out of the factory building.
https://story.nakagawa-masashichi.jp/wp-content/uploads/2017/10/tamahagane02.jpg
Freshly-smelted Tamahagane. Being raw iron, it oxidizes quickly.

Steel produced this way in the West is called “bloom steel.” Blacksmiths hammer, fold, and re-hammer these crumbly lumps to remove impurities and reduce/distribute desirable carbon forming the more homogeneous Tamahagane steel. This webpage has some interesting photos of tamahagane.

Related image
A clump of Tamahagane early in the forging process. Most of this material will be lost as waste before a useful piece of steel is born.
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After the Blacksmith hammers the raw clumps of Tamahagane hundreds of times, he then forms it into numerous small flat steel patties, which he breaks into the pieces shown in this photo in preparation for forge-welding them into a single larger piece of steel that he can then forge into a blade.

Tatara furnaces are still operated today producing Tamahagane in limited quantities for use by registered sword smiths. Tool blacksmiths use Tamahagane occasionally too out of interest in traditional materials and methods. It is expensive and difficult to work, with lots of waste.

A sawsmith who was active both before and after the availability of British steel on the island of Shikoku in Japan is recorded as saying that imported foreign steel increased saw production efficiency in his area tenfold. Clearly, Tamahagane was very labor intensive.

Mr. Kosuke Iwasaki, a famous metallurgist and blacksmith, described forging Tamahagane as being like “hammering butter” because it flattened and spread too quickly and unpredictably, at least compared to modern steels.

Besides its peculiar forging characteristics, compared to modern tool steels Tamahagane is a difficult material infamous for being easily ruined and extremely sensitive to temperature during all phases of forging and heat treatment.

In use, tools made from Tamahagane behave differently from modern commercial steel, or so I am told. I own and use a straight razor custom forged from Tamahagane for me many years ago by Mr. Iwasaki. I also own antique Scheffield and German razors, but my Iwasaki razor puts them all to shame in terms of sharpness, edge retention, and ease of sharpening. I also own a couple of antique Tamahagane saws, but I have not used them much, nor have I used Tamahagane chisels, planes or knives, so my experience is limited to this one wickedly sharp little blade.

My beloved Tamahagane cutthroat razor by Iwasaki

Why do I bother Gentle Reader with this story of ancient techniques and obscure products no longer viable? Simply because Tamahagane and the cutting tools and weapons it was once used to produce had a huge practical and cultural influence on both Japanese history and the Japanese people’s attitude towards weapons and cutting tools, in your humble servant’s opinion.

Although imported Western steel served Japan well during its advance to modernity, the memory of the performance of cutting tools made from Tamahagane remained alive in the national memory. Indeed, I am convinced the Japanese people’s love and fear of sharp things is not only psychological but genetic, although I have not seen any studies on the “sharpness gene.” But that is a story I will save for the next time we are enjoying a mug of hot coco together around the iori fire on a moonlit Autumn night. May that evening come soon.

Steel Production in Modern Japan

Enough ancient history. Let’s shift our focus to more modern steels.

When Japan began to mass-produce commercial steel from imported pig iron using modern techniques, the first tool steel made was identical to Western steels, including the impurities. These are still available today as the “SK” series of steels as defined by Japan Industrial Standards ( JIS).

Eventually, to satisfy the irrepressible sharpness gene of their domestic customers, Japanese blacksmiths and tool manufacturers pressured Japanese steel companies to produce steels with fewer impurities and with performance characteristics approaching traditional Tamahagane.

Rising to the challenge, Hitachi Metals endeavored to replicate the performance of Tamagane using modern smelting techniques and imported pig iron and scrap metal instead of expensive and environmentally unsustainable satetsu.

Ingots of Swedish pig iron

Hitachi purchased and modernized an old steel plant in Yasugi for this purpose. They formulated the best steel they could make using the best pig iron they could find, mostly from Sweden, an area famous for hundreds of years for producing especially pure iron ore. The results were Shirogami Steel (pronounced she/roh/gah/mee/koh 白紙鋼), Aogami Steel (pronounced aoh/gah/mee/koh 青紙鋼), and Kigami Steel (pronounced kee/gah/me/koh and written黄紙鋼) meaning “Yellow Label Steel.” Later, they developed Aogami Super steel (青紙スパー ) and Silver Label Steel (stainless steel). Each of these products are available in various subgroups, each having a unique chemical formulation.

For a time, Hitachi marketed these steels with the “Tamahagane” designation. Problematic, that. Indeed, many saws and knives were stamped “Tamahagane” when these steels were first introduced.

With the increased popularity of Japanese knives overseas, several Japanese manufacturers have once again adopted this problematic practice of naming the steel their products are made from as “Tamahagane” despite being made of common steels and even stainless steels. Because these spurious representations were and continue to be made for the purpose of increasing profits for companies that clearly know better, in your humble servant’s opinion even the stinky label of BS is too good for them.

Caveat emptor baby.

Chemistry

We tend to think of steel as a hard metallic thing, but lo and behold, ’tis a chemical compound. Few chemicals humans make are absolutely pure, and while White Label, Blue Label, and Yellow Label steels have exceptionally low amounts of undesirable contaminants, they do exist. Dealing with the results of these impurities has been the bane of blacksmiths since the iron age.

The most common undesirable impurities include Phosphorus (reduces ductility, increases brittleness, and messes with heat treating), Silicon (a useful chemical but too much decreases impact resistance), and Sulfur (reduces strength, increases brittleness and warping). Obviously, something must be done about these bad boys.

Some people imagine that, through the Alchemy of Science, impurities are simply “disappeared” from steel during smelting. While some impurities can be eliminated through heat and chemical reactions, it is not possible to reduce the content of those listed above to insignificant levels through smelting alone.

Undesirable chemicals can be tolerated in steel to some degree because, like arsenic in drinking water and carbon monoxide in air, below certain levels they cause no significant harm. The best solution we have discovered is to reduce the concentration of impurities to acceptable levels by using ore and scrap that contains low levels of impurities to begin with, and constantly test, and reject or dilute the ”pot” as necessary to keep impurities below acceptable levels. This practice is known as “Solution by dilution.”

White Label steel is plain high-carbon steel without other additives, while Blue Label, Yellow Label, Silver Label, and Aogami Super steels have various chemicals added to achieve specific performance criteria. Please see the flowchart below.

Production Flowchart of White Label, Blue Label, and Super Aogami Steels
A flowchart outlining the manufacturing process

Another technique used to mitigate the negative effects of impurities found in steel ore is to add chemicals to the mix. Chrome, molybdenum, vanadium, tungsten and other chemicals are added to create “high-alloy” steels that can be more predictably forged and heat-treated, are less likely to crack and warp, and will reliably develop useful crystalline structures despite detrimental impurities. Such high-alloy steels can reliably produce useful tools in mass-production situations by untrained labor and with minimal manpower spent on quality control. But no matter the hype, such chemicals do not improve sharpness or make sharpening easier.

If you look at the table below, you will notice that White Label and Blue Label steels both have the same minute allowable amounts of harmful impurities such as Silicon, Phosphorus, and Sulfur.

Chemical Table of White Label, Blue Label and Aogami Super Steels

Product Designation Shirogami 1 (White Label 1)Shirogami 2 (White Label 2)Aogami 1 (Blue Label1)Aogami 2
(Blue 2)
Aogami Super
Carbon1.3~1.4%1.20~1.30%1.30~1.40%1.10~1.20%1.40~1.50%
Silicon0.10~0.200.10~0.200.10~0.200.10~0.200.10~0.20
Manganese0.20~0.300.20~0.300.20~0.300.20~0.300.20~0.30
Phosphorus<0.025<0.025<0.025<0.025<0.025
Sulfur<0.004<0.004<0.004<0.004<0.004
Chrome0.3~0.050.20~0.050.30~0.05
Tungsten1.50~2.001.00~1.502.00~2.50
Molybdenum0.3~0.5
Vanadium
Cobalt
Annealing Temp °C740~770°cooled slowly740~770°cooled slowly750~780°cooled slowly750~780°cooled slowly750~780°cooled slowly
Quench Temp°C760~800°water760~800°water760~830°water or oil760~830°water or oil760~830°water or oil
Tempering Temp°C180~220°air180~220°air160~230°air160~230°air160~230°air
Hardness HRC>60>60>60>60>60
Primary UsagesHighest-quality cutlery, chisels, planesHigh-quality cutlery, chisels, axes, sicklesHighest-quality cutlery,  planes, knivesHigh-quality cutlery, planes, knives. sicklesHigh-quality cutlery,  planes, knives
Chemical Table of White Label and Blue Label steels as well as Aogami Super (this table can be scrolled left~right)

Carbon of course is the element that changes soft iron into hardenable steel, so all five steels listed in the table above contain carbon, but you will notice that White Label No.1 has more carbon than White Label No.2. Likewise, Blue Label No.1 has more carbon than Blue Label No.2.

The greater the carbon content, the harder the steel can be made, but with increased hardness comes increased brittleness, so White Label No.1 is likely to produce a chisel with a harder, more brittle blade than one made of White Label No.2.

Accordingly, White Label No.2 steel makes a wonderful saw, but sawblades forged from White Label No.1 tend to be fragile unless the blacksmith removes excess carbon during forging to improve toughness.

In the case of chisels, plane blades, and kitchen knives intended for professional use, White Label No.1 is the first choice followed by Blue Label No.1 steel.

Where high performance at less cost is required, Blue Label No.1 or Blue Label No.2 are often preferred.

With impurities and carbon content the same, the chemical difference between White Label No.1 and Blue Label No. 1 then is the addition of chrome and tungsten, elements which make the steel tougher, much easier to heat treat, and reduce warping and cracking, thereby yielding fewer defect with less work. Chrome, and especially tungsten are expensive chemicals that make Blue Label steel more expensive to purchase than White Label Steel steel, but with easier quality control and fewer rejects, overall production costs are reduced.

All things considered, and this is a critical point to understand, compared to White Label Steel, Blue Label steel is easier to use, and more productive despite being a more expensive material. Indeed, many blacksmiths and all mass-producers prefer Blue Label steel over White Label Steel, when given a choice, because it is easier to use and more profitable, not because it makes a superior blade.

Many wholesalers and retailers insist that Blue Label steel is superior to White Label Steel because it is costlier and contains elements that make it more resistant to wear and abrasion intimating that it will stay sharper longer. To the easily deceived and those who do not follow this blog this may make perfect sense. But when wise Gentle Readers hear this sort of tripe they will know to gird up their loins and ready their BS shovels to keep their heads above the stinky, brown flood.

Wise Gentle Readers who choose blades forged from Blue Label Steel will do so because they know that Blue Label steel makes a fine blade at less cost than White Label Steel, not because Blue Label Steel blades are superior in performance. Moreover, regardless of the steel used, they will always purchase blades forged by blacksmiths that possess the requisite dedication and have mastered the skills and QC procedures necessary to routinely produce high-quality blades from the more difficult White Label Steel.

Quenching & Tempering

The process of hardening steel, called “heat treatment,” is key to making useful tools. Modern high-alloy steels vary in this regard, but in the case of plain high-carbon steels, the two primary stages (with various intermediate steps we won’t touch on) of heat treatment are called “quenching” and “tempering.”

In the case of quenching, the steel is heated to a specific temperature, maintained at that temperature for a set amount of time, and then plunged into either water or oil, freezing the dissolved carbon in the steel into a rigid crystalline structure containing hard carbide particles. After this process the steel is quite hard, indeed brittle enough to shatter if dropped onto a concrete floor, for instance; Basically useless.

To make the steel useful for tools it needs the next step in the heat-treatment process, called “tempering,” which adjusts the rigid crystalline structures created during the quench, losing some carbides, but making the steel less brittle and much more tougher. This is achieved by reheating the steel to a set temperature for a set period of time and then cooling it in a specific way. This heating and cooling can happen in air (e.g oven), water, oil, or even lead. All that really matters is the temperature curve applied. Every blacksmith has their own preferences and procedures.

With that ridiculously overly-simplified explanation out of the way, let’s next take a gander at the “Quench Temp” row in the table above which indicates the acceptable range of temperatures within which each steel can be quenched (using water or oil) to successfully achieve proper hardness. If quenching is attempted outside these ranges, hardening will fail and the blade may be ruined.

In the case of White Label steel, the quenching temperature range is 760~800°C, or 40°C. Please note that this is a very narrow range to both judge and maintain in the case of yellow-hot steel, demanding a sharp, well-trained eye, a good thermometer, proper preparation, and speedy, decisive action. Just to make things worse, even within this allowable range a shift of temperature too far one way or the other will significantly impact the quality of the resulting crystalline structure, so the actual temperature variation within the recommended quench temp range an excellent blacksmith must aim for is more like ± 5˚C.

Compare this range of quenching temps to those for Blue Label steel with an acceptable quenching temperature range of 760~830°C, or 70°C of range, a 75% increase over White Label steel.

Let’s next consider the recommended Tempering temperatures.

For White Label steel, the tempering temperatures are 180~220°C, or 40°C of range. Blue Label steel’s temperatures are 160~230°C, or 70°C of range, once again, a 75% greater safety margin.

The practical temperature range for quenching and tempering Blue Label steel is still quite narrow, but this increase in the allowable margin of error makes the job a lot easier, making Blue Label Steel much less risky to heat-treat successfully than White Label steel.

Judging and maintaining proper temperatures is where all blacksmiths, without exception, fail when they first begin forging and heat-treating plain high-carbon steel. The guidance of a patient master, time and perseverance are necessary to develop the knack.

I hope this partially brings into focus the challenges these two steels present to the blacksmith.

If you seek greater adventure, please look online to find similar data for many of the popular high-alloy tool steels. Comparing those numbers to White Label steel and Blue Label steel will help you understand why mass-producers of tools, with their lowest-possible-cost mindset, limited quality control efforts, and factory workers instead of trained blacksmiths, prefer them.

Warpage & Cracking

A huge advantage of chrome and tungsten additives is that they reduce warpage and cracking significantly. This matters because a blacksmith using plain high-carbon steel like White Label steel must anticipate the amount of warpage that will occur during quenching and shape the chisel, knife, or plane blade in the opposite direction so that the blade straightens out when quenched. This exercise requires a lot of experience to get right consistently, making White Label steel steel totally unsuitable for mass-production.

Steel is an interesting material. When yellow hot, the carbon is dissolved and moves relatively freely within the iron matrix. Anneal the steel by heating it and then cooling it slowly and the carbon molecules will migrate into relatively isolated clumps with little crystalline structure leaving the steel soft. But if the steel is heated to the right temperature and suddenly cooled by quenching, the carbon is denied the time and freedom it had during the annealing process, instead becoming locked into the iron matrix forming a hard, rigid crystalline structure. This iron/carbon crystalline structure has a significantly greater volume than pure iron, which is why the blade wants to warp when quenched.

Adding chrome and tungsten and other chemicals reduces this tendency to warp.

An interesting example is a sword blade. A Japanese sword blade is typically shaped either straight or curved towards the cutting edge before quenching, but during quenching the blade warps and curves without encouragement from the blacksmith. The skill and experience required to pre-judge the amount of this warpage and the resulting curvature of the blade, and then compensate while shaping the blade before quenching to achieve the desired curvature post-quench is not something one learns in just a few months or even years.

This image has an empty alt attribute; its file name is IMG_7583-1024x683.jpg
A Japanese swordsmith with a blade made from high-carbon Tamahagane poised for quenching. Notice how straight the blade is. He has invested months of work into this blade to this point and a misjudgment or even bad luck in the next second can waste it all. Not a job for the inexperienced or timid.
Related image
After quenching, the resulting warpage is dramatic, but according to plan. The swordsmith must anticipate this distortion and shape the blade to compensate prior to the quench if he is to avoid unfortunate results. Notice the mud applied to the blade before quenching to control the formation of crystalline structures and achieve differential hardness. Tool blacksmiths are faced with the same challenges on a smaller scale but more frequently.

Unlike Tamahagane, however, modern commercial steels containing alloys like chrome and tungsten warp much less, and suffer far fewer shrinkage cracks.

Aogami Super is another steel in the table above. It’s an interesting steel, containing more carbon than both White Label steel and Blue Label steel and a lot more tungsten than regular Blue Label steel. Consequently, it is even more expensive. Aogami Super was originally developed as a high-speed tool steel especially resistant to wear. There are much better steels available for this role now, but Aogami Super is still hanging in there.

But all is not blue bunnies and fairy farts because high-alloy steels have some disadvantages too. 

Those who hype high-alloy steels always praise to the heavens the “wear-resistant” properties Chrome and Tungsten additives afford. When the subject is woodworking handtool blades, however, please read “wear resistance” to mean “a bitch to sharpen,” and/or “not very sharp.”

Tungsten makes the steel warp less and expands the heat-treat and tempering temperature ranges significantly leading to fewer defects during production. But the addition of tungsten also produces larger, tougher crystals that simply can’t be made as sharp as White Label No.1, and that makes the blade much more difficult, unpleasant, and time consuming to sharpen, all while wasting more sharpening stone material in the process.

White Label steel has no additives other than carbon. It does not need additives to compensate for or to dilute impurities because its production begins with exceptionally pure pig iron, mostly from Sweden (for many centuries the source of the purest iron in the world), and carefully tested and sorted scrap metal. Both White Label and Blue Label steels, if properly hand-forged and heat treated by an experienced blacksmith with high quality standards, will have many more and much smaller carbide clumps distributed more evenly throughout the iron crystalline matrix producing a ” fine-grained” steel of the sort coveted since ancient times

Nearly all the tool steel available nowdays contains high percentages of scrap metal content. Scrap metal is simply too cost effective to ignore. Careful testing is the key to using scrap metal advantageously.

Performance Differences

Gentle Reader may have found the historical and chemical information presented above interesting, but they do not really answer questions you may have about the performance differences between these steels, and when presented a choice, which one you should purchase. Your humble servant has been asked and answered these questions hundreds of times, and while only you can decide which steel is best for you, I will be so bold as to share with you the viewpoint of the Japanese blacksmith and woodworking professional.

Long story short, in the case of planes and chisels, the typical choices of steel are still White Label No.1, White Label No.2 or Blue Label No.1. These steels will not be available much longer.

If you are dealing with honest blacksmiths and honest/knowledgeable retailers with experience actually using, not just talking about and selling, tools, you will have observed that a specific plane blade, for instance one made from Blue Label steel will cost less than the same blade made from White Label steel, despite Blue Label steel being more costly.

At C&S Tools a 70mm White Label No.1 steel plane blade cost 77% more than one made from Blue Label No.1. This means that the blacksmith’s average cost in terms of his labor (overhead, forging and shaping being the same) is also around 77% higher over Blue Label steel, a direct reflection of his potential additional time expenditure due to risk of failure.

White Label steel simply warps and cracks more, but when failure occurs it only becomes apparent after all the work of laminating, forging and shaping are complete. Ruined steel cannot be reliably re-forged or re-used, so all the material and labor costs up to the point of failure are simply wasted like an expectation of honesty in a California politician. It is not a material for careless people or newbies. The steel that is, not the politician who is certainly irredeemable.

So if White Label steel blades are riskier to make, with more wastage, and therefore more expensive, what are the performance characteristics that make White Label steel blades a favorite with professional Japanese craftsmen? Two primary reasons: First, properly made White Label steel blades can be made sharper. This makes the craftsman’s work go quicker and more precisely.

Second, properly made White Label steel blades are easier, quicker and more pleasant to sharpen. That sums it up. To some people this difference matters a great deal; To others, not so much.

Is White Label steel worth the extra cost? I think so, but the performance differential is not huge, and only someone with advanced sharpening skills will be able to take full advantage of the difference. For most people on a tight budget, or in the case of woodworking situations where sharpness is not critical, and sharpening speed and pleasure are not driving factors, then a less-expensive Blue Label steel blade is perhaps a better choice. It absolutely makes a fine tool that does a great job of cutting wood.

Let’s shovel some more BS out of the way by performing the mandatory experiment of taking a high-quality White Label steel blade and a high-quality Blue Label steel blade, sharpening them identically using the best stones and advanced technique, test them to cut some wood, and then considering the answer to the following two important questions:

Question 1: Will the additional sharpness of a White Label steel plane blade create a smoother, shinier finish surface on wood than a Blue Label steel blade?

Answer 1: Definitely no. But since it started out a little sharper, it will cut a little better a little longer.

Question 2: In the case where edge-retention, cutting speed, and cutting precision are more important than a shiny finish, which absolutely applies to chisels and knives, will the additional sharpness of a properly made and proficiently sharpened White Label steel blade improve a tool’s cutting speed, edge-retention, precision and control?

Answer 2: Absolutely yes. On condition that the user possesses the skills to achieve and maintain that extra degree of sharpness. There is a reason sharpening has always been the first essential skill in woodworking.

These are the reasons why we don’t even offer chisels made from Blue Label steel, or even White Label No.2 with its lower-carbon content, and resulting reduced hardness.

But whether plane blade, chisel or knife, a properly forged and heat-treated blade made by an experienced professional blacksmith from simple White Label steel will always be quicker and more pleasant to sharpen than if made of Blue Label steel with its added sticky chrome and hard tungsten. To the professional that has the need for the additional sharpness as well as the skills necessary to produce and maintain it, that’s a difference many find worth the extra cost.

I daresay many of our Beloved Customers agree.

Related Information

Gentle Readers may find Hitachi Metal’s catalogue about their tool steels interesting. A PDF can be found at this LINK. Sorry it’s in Japanese. The first metal in the top row is White Label No.1 steel. The Quench temp shown is 760~800˚C and the tempering temp is 180~220˚C. The hardness is 60+ Rc.

You may also want to check out this article by Niigata Prefecture’s Research Center which shows some interesting details as well as pictures.

The steel tested is Blue Label No.2 steel (row 6 in the Hitachi catalogue pdf). It has added chrome and tungsten to reduce warping and increase the range of quenching temperatures. They heat-treated samples and listed the results for 7 of them. In each case, the quench temp varied from 750˚~900˚C (1382˚~1652˚F) in water, but the tempering temp was kept constant at 180˚C (356˚F) in air for one hour. Figure 4 at 775˚C (1427˚F) shows the best, finest, most uniform crystalline (Austentite) structure. Lower temps are not as good. Higher temps are worse. 25˚ one way or the other made a big difference. And remember this is Blue Label No.1 steel, which is much less sensitive to variations in temp than White Label No.1 steel. When using these steels, experience talks and BS walks.

There has been some bad news lately about Hitachi Metals. I won’t go into all the details, but Hitachi Metals announced in October 2020 that it’s planning to reduce its workforce nationwide by 3,200 employees. The likely impact on the Yasugi plant has not been announced.

YMHOS

A cross-section of the Eidai tatara furnace (also pictured at the top of this article) with human-powered blowers to right and left. The central furnace shows satetsu as the first layer resting on charcoal with the fire below. More layers of satetsu and charcoal are added as the process moves forward. The resulting mass of Tamahagane settles to the bottom of the furnace, but does not drop into what appears to be, but is not, a void below.

YMHOS

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Relevant Posts

Tool Maintenance: Corrosion Prevention

A Rusted Plane Blade by Hatsukuni. What did it do to deserve such horrible neglect?

“How dull it is to pause, to make an end,
To rust unburnish’d, not to shine in use!
As tho’ to breathe were life!”

Alfred Lord Tennyson, Ulysses

Between damaged tools and guns, corrosion prevention has been a high priority for your humble servant over the years motivating me to purchase many corrosion-prevention products and test them in various climates. After climbing mountains of hype and swimming floods of BS I think at last I have something of value, perhaps even the genuine article, to share with Gentle Readers.

There are three aspects of corrosion prevention for steel tools we will address in this article: Corrosion due to sharpening, corrosion due to handling, and corrosion due to storage.

But first, to help Gentle Reader understand the basis for the measures I will recommend below, allow me to explain my sharpening philosophy.

Tool Philosophy

The word “philosophy” is of Greek origin and means the “love of wisdom.” I won’t flatter myself that I developed any original wisdom about maintaining tools, because the truth is I stole most of what I know from better men and the rest came ipso facto from my own screw-ups. Embarrassment is a fine teacher.

Professional craftsmen have no choice but to constantly maintain and repair the tools of their trade, but necessary or no, clients and employers often resent the time craftsmen they hire spend maintaining tools during the work day. After all, they are paying them to make a product, not to fiddle with tools. The perceptive craftsman will strive to understand his Client’s perspective if he wants to be trusted with profitable repeat work.

Therefore, I don’t sharpen, fettle, or repair my tools at the jobsite anymore than is absolutely necessary, and never in front of the Client or employer. This is not some feel-good yuppy-zen BS, but a serious, concrete work philosophy with physical and financial consequences. It was taught to me by experienced craftsmen in America and Japan, all since retired to the big lumberyard in the sky, who knew what they were about. It has served me well.

So how do I keep working when blades dull, planes stop shaving, power tools stop spinning and bits stop biting? Whenever possible I have multiple saws, planes and chisels in the types/sizes critical for that day’s work, and even extra bits and power tools on-hand, so that if a particular chisel or plane becomes too dull to get the job done, or a bit breaks, or a circular saw, for instance, goes tits-up, I need only pause work long enough to retrieve a sharp, ready to rock-n-roll replacement from my toolbox or tool bag.

This means I must purchase, sharpen, fettle and carry around more tools than I am likely to use during that workday. But since my tools are partners that earn their keep, it is not wasted money or effort. In fact, this philosophy has resulted in tool-maintenance habits that I believe ultimately save me time and money while improving my work efficiency all while reinforcing my Client’s or employer’s confidence in me, just as the old boys said they would.

Of course, after a few days of continuous work I will have accumulated multiple blades that need sharpening, so if I am to keep making sawdust I must sharpen them in batches of 5~10 at a time. And because I sharpen in batches, as do professional sharpeners, I have given great thought over the years to maximizing positive results such as speed, sharpness achieved, and economical use of stones while minimizing negative results such as rusted steel. I humbly encourage Gentle Readers to give these matters just a few seconds of consideration. What have you got to lose besides steel?

Corrosion Prevention: Wet Sharpening

The bevel of the Hatsukuni blade shown above. Lovely colors.

The corrosion risk to tools when sharpening is corrosion caused by residual water in the scratches, cracks and crevices of the blade, as well as accumulated chlorine from tap water, promoting rust, especially at the very thin cutting edge. Yes, that’s right, I’m more worried about corrosion dulling the cutting edge than of it creating red spots elsewhere on the blade.

When sharpening a batch of blades in my workshop, after a blade is done on the final finish stone, I dry it with a clean paper towel, apply a few drops of Corrosion Block, smear it around on the blade to ensure a complete coating, and set it aside to draw water out of the pores and seal the steel. It works.

Corrosion-X is another good, but stinkier, product. Neither is good enough long-term, however.

After the blades have sat for a while, usually at the conclusion of the batch, I wipe off the CB and apply CRC 3-36. This is a paraffin-based corrosion preventative that floats out water. Paraffin won’t evaporate or wick-off and is the best product I have found to prevent rust developing on a clean, moisture-free surface.

CRC 3-36 sprays on easily and soaks into everything, and if allowed to dry, will give good long-term protection, as in years. It’s especially good for saw blades because it gets deep into the teeth. But you don’t want to apply it to anything even a little wet with water because paraffin will seal it in promoting rust. Ergo, Corrosion Block first.

There are many rust-prevention products on the market, so I am not suggesting CRC3-36 is the best, only the one I prefer, partly because O Mistress of the Blue Horizons doesn’t object to the smell too strongly if it wafts into her holy chambers from the workshop. If I use Corrosion-X, however, she bars the door with a broom, bayonet fixed, and makes me strip before she’ll let me back into the house. A gentle flower, indeed. But I digress.

This system works fine for short-term, and even for long-term storage if I wrap the tool in newspaper or plastic to protect the coating.

When sharpening in the field, or if I will be using the tool right away, I don’t bother with spray products, but just strop the blade on a clean cloth or the palm of my hand to generate friction heat, apply some oil from my oilpot, and call it good.

If you don’t own and use an oilpot already I won’t call you an idiot, but I still remember the time long ago when that word was directed at me by someone I respected for not making and using one. He was right.

A useful trick I learned from sword sharpeners is to use chlorine-free, slightly alkaline water for sharpening. I mix Borax powder with distilled water in a plastic lab bottle to use to keep stones wet and to wash blades when sharpening. Washing soda works too. A little lye added to sharpening water will also increase its pH. Using such water will not entirely prevent corrosion, but it certainly slows it way down. Test it for yourself.

Corrosion Prevention: Handling

We sometimes pull out a chisel, saw, or plane blade to gaze upon it. They are lovely creatures, after all. There are two things to be aware of when doing this, however.

Recall that the adult human body is comprised of approximately 60% water, some of which is constantly leaking out of our skins mixed with oils and salts. When you touch bare steel with your hands, skin oils, sweat, and the salt contained in sweat stick to the steel and will cause rust. It’s only a matter of how quickly and deeply.

The solution is to avoid touching bare steel you will later store away with bare fingers, and if you do touch the blade, wipe it clean and apply some oil from your oilpot or spray can right away before returning it to storage.

Gentle Reader may be unaware, but there can be no doubt that harsh words not only hurt the tender feelings of quality tools, but can directly damage them. How do I know that rude language offends steel tools, you say? Well, I have ears don’t I? In addition, over the years I learned a thing or two from professional Japanese sword sharpeners and evaluators, who are even more obsessed with rust than your paranoid humble servant, no doubt because of the high financial and historical costs of corrosion in rare and expensive antique weapons.

With the gift to the entire world of the Wuhan Virus from the Chinese Communist Party, we have all become more aware of the human tendency to constantly spew droplets of bodily fluids, often containing nasty bugs, into the air around us sometimes with unpleasant consequences. A handsaw can’t catch the Commie Flu, but fine droplets may find their way to the steel surface when we talk to them or around them. Corrosion ensues.

In Japan it is considered rude to speak when holding a bare sword. Indeed, it is SOP to require viewers who will get close to a bare blade to place a piece of clean paper between their teeth to confirm the mouth is indeed closed and not spewing droplets of spit onto the blade.

I am not exaggerating the cumulative long-term damage fingerprints and moisture droplets expelled from human mouths and noses cause to steel objects. Any museum curator can confirm.

How does this all apply to woodworking tools? If Gentle Reader takes a tool out of storage and either talks to it, or to humans around it, please wipe it clean, apply oil, and rewrap it unless you will be using it immediately.

Tools deserve respect. Perhaps I’m superstitious, but I’m convinced that if we avoid rudely smearing salty sweat or spraying globs of spittle that would cause our tools to turn red and go away, they in turn will be less inclined to cause us to leak red sticky stuff. Some tools are vindictive if offended, donchano.

Corrosion Prevention: Storage

The air on earth contains dust and moisture. Dust often contains abrasive particles harder than steel as well as salts and other corrosive chemicals. We must keep these particles and chemicals away from our tools.

Air also contains moisture that, given access and a temperature differential, can condense on steel tool blades causing condensation rust.

Your humble servant discussed these matters in length in earlier articles about toolchests, but a critical criteria of proper storage is to prevent dust from landing on tools, and to prevent the tools from exposure to airborne moisture and temperature differentials. A closed, tightly sealed, clean container, cabinet, toolchest or toolbox is better for tool storage than pegboards or shelves.

If Gentle Reader does not already have such a tool container of some sort, I urge you to procure or make one.

Tool Rolls

Your humble servant owns and uses tool rolls. They are handy for transporting tools such as chisels, files rasps and saws, but they have limitations Gentle Readers need to be aware of.

The first problem with tool rolls is that they appear to protect the cutting edges of chisels and saws, but that is only wishful thinking because the delicate and dangerous cutting edges are only hidden behind a thin layer of cotton or leather. Guess what happens if you drop a cloth tool roll of sharp chisels onto a concrete slab.

If you bump a tool roll of chisels against another tool, then brush your hand against the now exposed but hidden cutting edges while digging in your toolbox, sticky red stuff may get everywhere. Will the bloodshed never end!?

Do tool rolls protect tools against corrosion? No, in fact they can make it much worse because fibers in contact with steel, especially organic fibers such as cotton, can wick moisture to the steel producing corrosion. Please see the photos above.

Leather tool rolls can be especially bad in some cases because of residual tanning chemicals.

I’m not saying don’t use tool rolls, only to be aware of their limitations and use them wisely.

As mentioned above, I do use tool rolls in the field. The trick to preventing rusted blades is to insulate them from the fabric, so I make little plastic liners from the hard but flexible plastic used for theft-proof retail product packaging that fit into the pockets. Just a strip of plastic cut wide enough to fit into the pocket tightly and folded in half. Besides preventing rusty blades (the crowns will still rust) these little liners make it much faster and easier to insert blades into the pockets without cutting the tool roll. They also help prevent blades from cutting through the cloth or leather. The price is right too.

If you need to use tool rolls for long-term storage, I recommend you clean the tools, coat them with a paraffin-based rust-prevention product, and wrap them full-length in plastic wrap before inserting them into the tool roll’s plastic-lined pockets.

If tools are faithful and profitable servants, indeed extensions of our hands and minds, don’t they deserve more from us while they are in our custody than a rusty, pitted, neglected ruin like the plane blade pictured above?

YMHOS

If you have questions or would like to learn more about our tools, please click the “Pricelist” link here or at the top of the page and use the “Contact Us” form located immediately below.

Please share your insights and comments with everyone in the form located further below labeled “Leave a Reply.” We aren’t evil Google, fascist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may crickets be my only friends.

Our erstwhile apprentice from the clothing-optional workshop has dropped a chisel into the water while sharpening, and laments the inevitable corrosion. Being bald as a bowling ball, I’m desperately jealous of her long hair, but it must get in the way when working the stones.

The Essential Oilpot

The Japanese Gennou & Handle Part 18 – Wood Selection

Stanley “Stan the Man” Musial, one of baseball’s greatest players and most consistent hitters.

Used to be that bats had thick handles and a big barrel. Then they found it’s not the size of the bat that gets the home run – it’s the speed with which you can swing it.

I think I had the smallest handle around. When I got my bats, I even trimmed them down. I used to scrape them. Some years later when I started getting older, I used to start with a 33 and in the summer it got down to 31 and then probably in September got down to 30.

Stan Musial

In the previous 6 posts in this series we guided Gentle Reader in creating a drawing of a high-performance, minimalist handle to fit your gennou head and body closely. 

The handle in this drawing may not fit your body and the way you work perfectly at first; It may require adjustment, but it is a good place to start. 

Keep this drawing so you can remember what you based the original design on to help you analyze and record improvements for your next new-and-improved handle.

With the initial design complete and recorded in your drawing, the next step in this epic adventure of love, lust and sawdust is to select a stick of wood. Oh joy!

Your humble servant will not be so forward as to recommend a specific wood Gentle Reader should use. Instead, I will examine some performance criteria worthy of consideration, and only then suggest some potential candidate species.

The quotes above by Stan the Man Musial, a famous baseball player and coach that made a career swinging wood fast and with great precision, are especially relevant to the subject of gennou handles.

Please remember that, just like a baseball bat, a slender handle will not endure unless it is made from the right wood and designed to handle the forces it will encounter.

Strength & Toughness

Hammer handles are subject to relatively high impact forces in use which produce stresses and vibration, so the wood must be not only strong, as in resistant to compression, tension and bending forces, but tough. It must also have properly oriented grain.

Softer woods are easy to work and feel good in the hand, but a tenon made from a soft wood such as pine, cedar, poplar or maybe even cherry, for example, will often loosen quickly as thousands of impact forces over time crush the cells.

In addition, since the fit between tenon and eye must be very tight indeed, the process of driving the tenon into the eye will not be easy. Your humble servant has broken more than one handle while attempting this. The last instance was a few years ago with a gennou handle I made from Chinese Mulberry, a wood cherished in Japan for fine cabinetry work and of which I am unreasonably fond due to it’s dramatic grain, its golden color when freshly cut, and the purplish-brown color it changes to over time. I knew it might be too weak for the job, but tried anyway. A sad waste of time and beautiful wood.

BTW, if you have the opportunity to use mulberry wood for cabinet or joinery work, by all means give it a try. I think you will be pleasantly surprised especially as the item made from the wood ages.

Chinese Mulberry Wood

The material you ultimately select must be both strong and tough, but it is important to understand the difference between strength and toughness when considering materials.

The term “tough” in engineering circles means a material has the ability to absorb energy and/or forces without permanently deforming or breaking. A tough wood will still deform and bend, but when the forces that caused it to deform/bend are removed, it will return to its original shape instead of being permanently bent or breaking. In the case of a handle, if it is tough, it will flex somewhat without rupturing.

Gentle Readers are, without exception, highly intelligent with a refined eye and therefore will of course be tempted to use beautiful, dark exotic hardwoods such as ebony, rosewood, bubinga, wenge, kingwood, snakewood, etc.. These are fine woods that make beautiful handles, but I don’t recommend them for a first handle due to their high cost and the likelihood that Gentle Readers will want to replace the first handle they make, and maybe even the second and third, as their skills and understanding of the ideal handle for their body and working style improves with time and experience.

And while they may have beautiful color, sexy figure, and great compressive strength, many exotic woods like ebony and rosewood may lack adequate toughness in some (but not all) cases, and crack easily. And the extra weight of such dense woods is seldom an advantage.

Your humble servant has used them successfully, and so won’t suggest they can’t make fine handles, but simply urge Gentle Reader to be cognizant of the higher risk of failure. If you choose to use an exotic hardwood, please be especially careful of runout, a subject we will discuss below.

Friction

If you consider the vibration and angular acceleration forces acting on the gennou’s head and handle, you will understand the wisdom of choosing a wood that has a high coefficient of friction. Take my word that it is embarrassing to have the head slip off the handle mid-stroke even if no one is watching.

Oily woods like teak lack adequate friction to keep head and handle attached, in my experience. Bocote is another wood that tends to allow Murphy to slip the head off and create unplanned openings in gypboard walls. (ツ)

Stability

Another important performance criteria to consider when selecting a species of wood is that it be stable and exhibit minimal expansion/contraction with humidity changes.

If a wood that forms the tenon connecting handle to head shrinks too much when the ambient humidity decreases, the head will of course loosen.

If the tenon swells too much when ambient humidity increases, the wood cells may be crushed inside the unblinking steel eye causing the tenon to lose the ability to spring back to its original dimensions when humidity again increases, eventually resulting in a loose head. To make matters worse, the handle will loosen up even more when the humidity drops again. Murphy does backwards somersaults and clicks his horny heels at the apex while cackling with demented glee when this occurs.

This detrimental plastic deformation is the big downside to kigoroshi in hardwoods. Let he who has ears to hear take notice.

I encourage you to use a wood with a low tangential/radial expansion/contraction ratio.

The traditional way to deal with tangential/radial expansion/contraction in tool handles such as hammers and axes is to orient the rings of winter wood in the tenon in the long axis of the hammer head/eye. I don’t think this matters much with small hammers with small eyes, but it can make a difference in larger hammer heads with long eyes.

Limb Wood

It is tempting to use limb wood or orchard trimmings to make handles, especially if the grain’s curvature matches the intended design. And leaving some of the natural bark in the grip area can be interesting too. In fact, there was a period a few years back here in Japan when, probably due to the kezuroukai effect, many people were making handles from Mountain Cherry wood with the dark red bark left attached in the grip area.

This is a grand idea, especially if it means you can procure good wood for free. But for heaven’s sake don’t use such wood until it is well-seasoned and stable or you may find your wall has a new dent and your bench dog and his fleas have fled, or your bench cat starts muttering to the iron pixies skulking in your shop about your parentage and the size of the bus you rode to elementary school. Cats are like that, you know.

Wood Grain and Runout

Grain runout is an important factor to take into account when selecting a piece of wood for a handle. A good definition of runout is as follows:

“Runout refers to the orientation of wood cells being other than parallel to the edge (face) of the board. Often difficult to detect visually, severe runout can be detrimental to strength and resistance to vibration and impact forces.”

When a board’s annual rings do not remain within the boundaries of a given pattern, be it straight or curved, the locations where the grain exits the pattern’s boundaries are called “runout.” This is an engineering term used in structural design that is applicable to selecting handle wood. In this case, it has nothing to do with the rotation of wheels and gears. Cracks tend to begin at runout locations and propagate quickly. Excessive runout can significantly reduce the ultimate strength of a board, especially when subjected to the impacts and bending forces of the sort tool handles experience. 

There are those who will dispute this structural reality, but they have done neither the engineering studies nor the destructive testing that would give their opinions value, and are herewith directed to proceed posthaste to a pharmacy to procure the salve Mifune Toshiro recommended to the tattooed criminals in the movie “Yojimbo” before educating them about pain.

Whatever wood you use, and this is extremely important, you want the grain runout to be minimal, especially in the tenon and neck. Ideally, the grain will exhibit zero runout through the tenon and neck and be curved to match the handle shape. In other words, the ideal stick of wood will have a high-percentage of fibers that are continuous from eye to butt. Such wood can be found but it may take time and effort and eye strain to find. Using riven wood is a traditional way to reduce runout and provide maximum strength. On the other hand, some gradual runout in the grip area is usually acceptable.

Here is wisdom: The key to judging runout is to not examine just the board, but more importantly the individual stick of wood you are considering using for a handle after it has been cut into a rectangular cross-section in preparation for layout because, only when you can see all four sides the handle’s entire length, will you be able to reliably judge runout. Murphy will make a fool of you if you let him.

The following link may be informative on the subject of runout: Link 1

Useful Woods

In Japan, the best traditional woods for tool handles are said to be Soraki and Ushikoroshi, both domestic ornamental bushes with white wood and plain-jane grain which are no longer grown commercially and are difficult to obtain. We have a few sticks in-stock for interested parties.

A Hiroki head with a Ushikoroshi wood handle

Nowadays Japanese White Oak is the standard handle wood in Japan. It is denser and stronger and whiter in color than its American and European counterparts, but the grain is quite plain.

Hickory is recognized world-over as the best generally-available material for handles, but it’s grain and color are boring. It should be easy for Gentle Readers to procure since it is sold as replacement tool and axe handles in most hardware and home centers.

Black Persimmon Planks

Other reliable options are Ash, the various species of White Oak, Maple, and Birch, etc..

I have made several handles from Black Persimmon, a fruitwood in the ebony family, yellowish in color but with a dramatic, smoky black grain. Black Persimmon has been highly prized in Japan for hundreds of years as a wood for high-end cabinetry. The grain and color are unique.

Since around 1900, American Persimmon was considered the best wood for golf club heads because of its toughness, the “pop” it gave the ball on impact, and its relative light weight compared to its toughness. It makes a great gennou handle. I am told it is still available in some areas.

A Kosaburo Classic-profile head with a Black Persimmon handle
A Kosaburo Modern-profile head with a Black Persimmon handle

I have also made handles from American Osage Orange, a dense, stringy wood used for bows and musical instruments that makes an extremely good handle, at least once the scary neon orange color mellows through exposure to sunlight. I highly recommend it, especially if you can get it for free, which shouldn’t be too difficult in the US Midwest where it was once used extensively for fenceposts and still grows like weeds around old fence lines.

Just make sure it has reached equilibrium moisture content before making a handle from it.

Top: A 100monme Hiroki Yamakichi head with a new and shockingly-colored American Osage Orange handle. Bottom: A 60monme Kosaburo Classic-profile head with a mellowed American Osage Orange handle.

Maple can make an excellent handle too. I used a stick of highly-figured tiger stripe Maple for the daruma gennou handle below, and another piece of Maple with only a little figure for the smaller daruma gennou further below.

A 80monme Hiroki Daruma head with a tiger maple handle (side view)
A 80monme Hiroki Daruma head with a tiger maple handle (face)
A 60monme Hiroki Daruma head with a tiger maple handle (side view)
A 60monme Hiroki Daruma head with a tiger maple handle (face view)

In the next post in this series we will layout our handle in preparation for making sawdust.

YMHOS

Stan the Man Musial. Please notice the skinny bat he used with great success.

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 the angry fleas of a thousand camels infest my armpits.

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The Strongmen Under the Veranda

Art is born of craftsmen. Art is not born of those called artists.

Tsunekazu Nishioka and Horin Matsuhisa “The Heart of Trees, the Heart of Buddha”

Having worked in architecture and construction in Japan for more than half of my life, your humble servant is fond of Japanese traditional wooden architecture. It has much to recommend it, not only for the visual beauty of the designs and the spacial experiences it often provides, but also the excellence of much of it’s execution, made possible through craftsmen’s skill with Japan’s excellent woodworking tools.

In this post we will examine a few details of Japanese traditional architecture, and the Japanese language phrase one structural member engendered, the origin of which most Japanese are unaware. Perhaps Gentle Readers will find this obscure phrase as interesting as your humble servant does.

The linguistically-intriguing architectural detail that is the primary subject of this article is a wooden structural member called the “en no shita no chikara mochi.”(縁の下の力持ち)which translates to “Strongman under the veranda.”

Some background is called for. As you can see from the photo at the top of this page, traditional wooden Japanese buildings are raised above the surrounding ground by a step or three with an ventilated crawl space beneath the floor. This is a practical feature commonly found in many countries, especially those with high groundwater levels, where it serves to keep soil dampness from penetrating the interior spaces thereby forestalling mold and wood rot.

In Japan, where exterior spaces, such as gardens, landscapes and even celestial spaces (e.g. moon viewing platforms) have been incorporated into buildings, the step up into the building is an important division between interior and exterior spaces. One may wear shoes into the entryway “genkan” of a building, but they must be removed before stepping up and entering the building proper. The genkan, therefore, being behind doors, is both an interior and exterior space. The wooden elevated veranda walkway around the perimeter of the building, called the “engawa” 縁側 in traditional Japanese architecture even moreso.

An engawa veranda in a traditional wooden structure. Notice the step-up from the ground level to the wooden veranda and an additional elevation change when entering the building’s interior with tatami-mat floors. Notice also the worse-for-wear sliding shoji screen doors to the left which separate interior and exterior spaces when closed, but expand the room into the garden when open. Please also notice, if you can, the groove cut into the floor of the veranda near the exterior edge in which lightweight wooden sliding doors called “amado,” meaning “rain doors” slide to enclose and protect the veranda when necessary. To the right of the veranda you can see a gravel-filled drainage trench constructed to receive rainwater dripping from the eaves instead of obtrusive, rudely gurgling rain gutters and pipes. Sitting on fragrant tatami mats, or on the wooden engawa floor with the shoji screens open of a spring evening or autumn afternoon while gazing out at a beautiful garden and listening to the sound of rainwater gently pattering on this gravel is a combination of sensory delights with which I hope Gentle Readers will someday be blessed.
Sorakuen in Kobe, Japan

The floor of the building is supported by a series of beams and purlins called “ Strongmen.” Those at the veranda are called “en no shita no chikaramochi” 縁の下の力持ち meaning “strongmen under the veranda.” In traditional Japanese architecture the veranda structure is designed so that these beams are both cantilevered and partially concealed creating a lightweight feeling, even giving the impression that the veranda floor is almost floating in air when viewed from some angles. The chikaramochi (chee/kah/rah/moh/chee) beams are seldom seen by the building’s residents, but without them, a building could not have a raised floor and would inevitably fail.

A phalanx of noble dragons supporting the first floor of the Taishakuten temple in Tokyo. In traditional Japanese architecture, ordinary uncarved beams supporting the floor in this way are called “En no shita no chikara mochi.”(縁の下の力持ち)which translates to “Strongman under the floor.” In the Japanese tradition, the dragon is a benevolent, noble creature that travels between oceans and heaven. The brackets supported on each dragon’s head in this photo represent clouds, as if the dragon team of strongmen are carrying the building through the heavens. In this case, the dragons have three toes on each foot, indicating that this is a private temple. Only dragons in imperial temples were allowed five toes.
Another noble dragon with waves at his feet and the kumimono clouds on his head. Amazing carving work.

Most Japanese people know and use the idiom without realizing it refers to this structural support.

To refer to someone as being a “Strongman Under the Floor” is to imply they are an “unsung hero,” or a person who quietly, selflessly and competently serves society and others by performing important but unseen tasks as a member of a team. From the Japanese dictionary it means “someone who toils diligently to support others in unseen ways and without recognition.” I salute all the strongmen under the floor, especially in the crafts and construction industry.

In our times we see an increasing trend for people in the public eye, especially actors, artists, musicians, politicians and journalists to display pyrotechnic levels of psychotic narcissism, the less talent and fewer accomplishments possessed the greater their frenzy to attract attention. These foul-mouthed, low-intelligence, often wealthy sociopaths, devoted to self-aggrandizement and the debasement of anything truly admirable, demand not only our unreserved celebration of their psychosis, but compliance with their ever-changing immoral opinions. In situations where individuals with a similar psychosis have managed to grab unlimited power, the resulting loss of innocent life has been horrendous beyond imagining. A former leader of the Soviet Union, himself a remorseless dictator dedicated to the destruction of Western democracies, enslavement of entire nations, and with the blood of millions on his hands once called such narcissists “useful idiots,” and made a science of how to foster and effectively use them to destroy entire nations. His work continues even today.

But while narcissists, sociopaths and their sycophant useful idiots receive all the attention, and sadly, praise, it is the stable, moral, selfless, hard-working common people that build and defend and perpetuate decent societies. In your humble servant’s opinion it is these good people that are the “Strongmen under the floor” that deserve our true respect.

The photos above and below show a happy team of noble three-toed dragons serving as “en no shita no chikara mochi” supporting the first floor of the Taishakuten Buddhist temple in Tokyo. A thankless but important task these several-dozen hand-carved zelkova-wood dragons perform with energetic poise and a toothy grin. Bravo!

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A phalanx of noble “strongmen” supporting a lavish veranda. These brave dragons straddle the waves of the oceans below them, and support wooden kumimono brackets which represent the clouds of heaven, on their prickly heads. The symbolism of these intricate carvings and complicated structural details is by no means haphazard.

Many professional woodworkers and blacksmiths are much the same as these dragons: inconspicuous, honest, hard-working, competently supporting the world within their scope without complaint, often with understated style.

YMHOS

The main entry into the Taishakuten temple. The carved figures at the top of the columns facing outwards to the left are Chinese Lions whose job it is to protect the holy precinct from demons and evil spirits. The figure with the elephant-like nose carved into the beam-end facing Gentle Reader is a mythical creature called a “Baku” 貘, a generally benevolent creature that eats bad dreams. The complicated brackets (called “kumimono”) supported on the columns have a structural purpose, of course, but in traditional Buddhist architecture they represent clouds, reflecting the link between the building and the heavens. Can’t have demons, evil spirits or bad dreams nesting up in there! Notice that, while the ends of the kumimono brackets have been painted white, the carved beams and columns are unvarnished, hand-planed, never-sanded Zelkova wood. Counter-intuitive though it may seem, hand-planed wood exposed to the environment lasts longer than if it was finished with abrasives and varnished or painted.

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.

Just ask the next baku you meet if it ain’t so. They can’t tell a lie you know.

The Japanese Gennou & Handle Part 17 – The Drawing Part 6/6

Dom Campbell’s in-progress atedai, and a few of the tools he used, including a most excellent gennou with a Kosaburo head and a handle he made himself.

Used to be that bats had thick handles and a big barrel. Then they found it’s not the size of the bat that gets the home run – it’s the speed with which you can swing it.

Stan Musial

In the previous five posts in this sub-series about making a drawing for a high-performance custom gennou handle, we measured various dimensions and incorporated them into our drawing. In this post we will bring everything together, and then discuss some of the strange features of this design, including a physics equation that drives it.

During this phase of the handle-making process you will have another opportunity to express the minimalist artiste lounging stylishly within your soul, probably wearing a cravat and sipping espresso languidly. C’est Magnifique!

The Sides

Let’s start work by drawing the butt’s width, determined in the previous post, on the plan view (upper half of the drawing above) centered on the handle’s centerline.

Next, once again in the plan view (upper half of the drawing above), draw two lines from where the tenon exits the eye to the butt.

Beginning at the grip area, draw curves from these two lines to to the right and left sides of the butt in a smooth transition, gradually expanding in width. The curvature/flair you produce will depend on the size of your grip, the width of the butt, and your sense of what makes a beautiful line. Feeling artistic yet? More espresso please.

Whither the Bulge?

Gentle Readers will have noticed from the drawings and photographs seen in this series so far that, unlike commercial handles, the handle we are designing does NOT exhibit a cancerous swell just below the eye. This is not a mistake. Remember, we are making a lean, mean, racing machine, not a nail bender with a sloppy eye and mass-produced tenon that needs wedges to hold it together.

This shape, with its narrow neck, flare towards the butt, and lack of the typical bulge below the eye strikes most people as strange, so an explanation may be useful.

To begin with, Japanese gennou heads of the quality assumed in this article are not secured with wedges, but by an extremely tight fit between the wooden tenon of the handle and the surfaces inside the precision-forged eye. Indeed, the fit should be so tight that, if by accident or some terrible oversight, one attempts to drive the tenon of a handle made from a wood too weak for the job into the head’s eye, the handle and/or tenon will fracture. Your humble servant has done this several times. Such a tight fit does not occur by accident. Wedges could only weaken the tenon and handle causing early failure.

To ensure this fit is indeed tight and secure, Gentle Readers must prepare the eye if the head is of lessor quality than the Hiroki or Kosaburo heads we carry, as described in previous posts in this series. If that work was necessary, we will assume it has already been completed.

Gentle Readers must use a strong, tough wood suitable to the task. The selection of wood will be the subject of the next post in this series.

They will also need to create a properly sized tenon on the handle’s end. These are critical points.

Because it is a craftsman’s hammer, not a wood butcher’s maul, there are no wedges to split the handle, and therefore no need for a tumor below the eye to both reinforce the sloppily-made handle and to keep the wedge from pushing the head down the handle.

Indeed, without the cancerous bulge, if the handle loosens sometime in the future, tapping the handle further into the eye will tighten it up, something a bulge would make impossible. Best to eliminate unsightly, unnecessary bulges entirely.

Air Resistance

Your humble servant has previously suggested that the handle we are designing will be a “high-performance tool,” indeed a “racing machine.” While not in the same class as a Formula-1 race car, air resistance is definitely a factor affecting performance, one impeded by an unnecessarily large hammer face, a thick, obese handle, and a bulge below the eye as is typical for commercial handles.

Why is air resistance an issue, you say? Of all the hand tools used in woodworking, aside from the long-handled axe, the hammer is the one that moves the fastest, and since air resistance varies with the square of the object’s velocity, hammers and axes are impacted by air resistance more than any other hand tools. Remember, we are talking about energy created by your body that is wasted by pushing air around unnecessarily.

For those Gentle Readers that enjoy math, the formula for calculating air resistance includes the area of the object, a drag coefficient specific to the object’s shape, and the object’s velocity squared. 

F = Force due to air resistance, or drag (N)

k = A constant that combines the effects of density, drag, and area (kg/m)

v = The velocity of the moving object (m/s)

ρ = The density of the air the object moves through (kg/m3)

CD = The drag coefficient, includes hard-to-measure effects (unit-less)

A = The area of the object the air presses on (m2)

We can’t control air density.

The total CD drag coefficient is a combination of the CDhead of the head and the CDhandle of the handle. We can reduce this combined Total CD by using a more aerodynamic steel hammer head instead of a huge, silly mallet, and by reducing the area of the handle pushing the air aside during the swing. I haven’t made the calculations, but the energy squandered by the excess drag of an obese handle over thousands of swings during a day’s work is not insignificant.

Another advantage of a slender neck on a hammer handle is the surprising reduction in vibration transmitted to the user’s hand, saving wear and tear on joints. This alone makes it a worthwhile improvement in my experience.

But all is not blue bunnies and fairy farts, I fear, for there are two downsides to a skinny super-model neck on a handle. First, if you tend to miss a lot when driving nails, errant heads may chew up the handle in an area where there is not much material to spare. Gentle Readers would be fully justified in blaming this damage on the malicious malfeasance of pixies, or the luck of Murphy, but my advice is: don’t miss.

The second downside to a slender neck in a gennou handle is that it’s inconvenient for choking-up on. But on second thought, that’s not a disadvantage to anyone except mountain trolls and grannies, bless their fluffy-white souls. The solution? Don’t choke up on the handle; The grip is the grip.

All Choked Up

Commercial hammer handles are a one-size-fits-nobody design, intended to accommodate many grip styles, apparently by many species, along most of the handle’s length. Holding the hammer like a hungry troll tenderizing a dwarf for the stewpot (perhaps with a delicate sprinkle of sage or a more bold glob of “floater” spice), and choking up on the grip like a near-sighted grandmother is the lowest-common-denominator design standard for commercial hammers, a crude detail simply not to be borne by C&S Tool’s Beloved Customers and the exceedingly refined Gentle Readers of this blog.

“They should be grilled and sautéed with a sprinkle of sage”

The ultimate goal of this exercise is to produce a hammer that fits Gentle Reader’s body perfectly, not every Tom, Burt or William that staggers into The Home Despot from the Ettenmoors. It will fit your arm, and your hand, and you grip without choking-up on it.

What’s wrong with choking up on the handle? Did I just hear you say: “If it’s good enough for Granny it’s good enough for me?” If so we may need to procure more of the salve Mifune Toshiro lamented not having.

Choking up on the handle is inefficient for two reasons. First, because it changes the balance of the hammer and your working rhythm (pendulum physics). This is bad.

Second, when you choke up on the handle, for at least a couple of strikes you lose the sense of the distance from your hand to the striking face’s center, reducing both your precision and confidence, and the energy imparted to the chisel or nail. Reestablishing the correct distance in your mind requires a glance at the hammer, an adjustment in your head, and an interruption in your hammering rhythm. All this nonsense is easily avoided by gripping the handle in the same location every time.

You have basically designed most of the grip’s details when you set the butt’s shape and dimensions, and the location of your palm’s heel, index finger, and pinkie finger. I suggest you leave well-enough alone for now, and, assuming this is your first custom handle, make it a tad oversized at first, and then whittle, shave, and sand it as you use it until it fits you perfectly.

In the next post in this series we will select a piece of wood from which to make our craftsman’s gennou handle. Soon we will be making sawdust… how exciting!

YMHOS

If you have questions or would like to learn more about our tools, please see the “Pricelist” link 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, facist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may the angry fleas of a thousand camels infest my armpits.

Previous Posts in The Japanese Gennou & Handle Series

Hasegawa Kosaburo and the “Classic Profile” Gennou Head

A 200monme (750gm/26oz) classic-profile gennou with a black persimmon wood handle. Notice the swollen area near the eye of this archaic design

“The Road goes ever on and on

Down from the door where it began.

Now far ahead the Road has gone,

And I must follow, if I can,

Pursuing it with eager feet,

Until it joins some larger way

Where many paths and errands meet.

And whither then? I cannot say”

J.R.R. Tolkien, The Fellowship of the Ring

In this post your humble servant will introduce a famous modern-day Japanese gennou hammer blacksmith and a somewhat archaic product he infrequently forged. It is our fervent hope to provide Gentle Readers some insight into the world of the Japanese blacksmiths of yesteryear.

Hasegawa Kosaburo

Let’s begin with some background about the gennou (hammer) blacksmith known as “Kosaburo.”

Hasegawa Kosaburo 長谷川幸三郎 was born Sakai Kosaburo in 1935 in Sanjo City in Niigata prefecture Japan, the third son of a pruning shear blacksmith. He married and was adopted into the Hasegawa family and changed his legal name from Sakai to Hasegawa, a tradition in Japan used to maintain genealogical lines in the case of acute male heir deficiency.

The Hasegawa family were blacksmiths that specialized in mass-producing hammer heads.

Kosaburo worked in the family business but eventually tired of factory work and began working with his adopted brother, Hasegawa Kanichiro, who later became famous for his “Hishikan” brand gennou heads. After 10 years of practical experience in both mass-producing and hand-forging gennou heads, Kosaburo decided to devote himself to the deceptively-difficult work of hand-forging high-quality gennou heads, eventually becoming independent under his own “Kosaburo” brand.

A more detailed description of Hasegawa Kosaburo’s life and work is found at this webpage. Sorry it’s in Japanese.

Here is a video of Hasegawa-san forging a modern-profile gennou with laminated steel faces, a common method worldwide when steel was still expensive. Seeing this I think you can understand how the swell discussed below was a standard feature of forged hammers throughout most of human history.

Mr. Hasegawa has since moved on to the big woodpile in the sky where he is probably cutting charcoal. His products are no longer being manufactured, of course, but even when he was active, Kosaburo products were widely recognized as the best-quality gennou heads ever produced in Japan. At this juncture, I believe Hiroki heads are the very best new heads available.

Kosaburo’s Students

Kosaburo trained two gennou blacksmiths that are still active today: Baba Masayuki (born 1949), who uses the brand name “Doshinsai Masaykui” (道心斎正行), and Aida Hiroki (born 1964), who uses the brand name “Hiroki” (浩樹).

Mr. Baba produces beautiful decorative gennou heads. Sadly, I am not fond of his products because, in my direct experience, sometimes the eyes are not true. Am I being too severe? Should I value external beauty foremost and wink at the ugly void where the handle attaches?

Here’s my thought process in the matter; You must judge for yourself. Decoration can compensate for many shortcomings, but the used car salesman’s schtick that “It isn’t a flaw, it’s a feature” doesn’t impress me, at least not in a tool as simple as a hammer head and at the prices for which his products sell. Kinda like the city slicker who paid a high price for a stunningly beautiful Arabian horse named “tripod” and justified its missing leg because it had three good ones left, and the hopping was not really that noticeable. For me, craftsmanship and functionality take precedence over decoration. But I won’t tell you what you should think because, well, that’s your wife’s job. (ツ)

Mr. Aida’s products, on the other hand, are less decorative but of accurate construction and hardness of the sort that makes the hearts of true craftsmen sing. Making a precise, properly-forged and differentially-hardened gennou head (hard face but soft body) is no mean feat. When I can’t get Kosaburo heads, Mr. Aida’s Hiroki brand are my next choice. The last I asked Mr. Aida, he had a three-year waiting list for his products. Very popular over here.

Most blacksmith’s shops are dark, dirty, smoky places like a dungeon in hell minus the demon torturers, lakes of blood, and the bitter stink of rotisserie lawyers, but when I visited Mr. Aida’s forge I found it to be neater, cleaner, and tidier than most CNC machine shops.

The Classic-profile Gennou Head

The head pictured in this article is the primary subject of this article. It’s an antique style seldom seen anymore, one that was once the standard shape for blacksmith-forged heads throughout most of the world. I like to call it the “classic profile” gennou head. It really doesn’t have a specific name in Japanese that I have been able to discover.

The polished areas at each striking face are non-functional vestiges of the laminated steel faces applied to gennou heads back when steel was very expensive.
Please be aware that, while new, this head is old-stock, at least 40 years old. Notice the eye. Not only are its dimensions perfect, but it is centered in the body and aligned with the head’s axis in both directions. Not an easy thing to do by hand in yellow-hot steel.

We have a few of these in-stock, but they are now serious collector’s items and pricey. Few were ever made in this style and I have never seen one in an auction. Please be aware that the head shown is old-stock, at least 40 years old. During those years in storage in a cardboard box the head developed some surface rust of the sort antique dealers call “patina” in reverent tones which is easily removed, but no deep pitting.

The shape is subtle. The swollen waist is a feature all hammer heads worldwide once exhibited, a remnant of the blacksmith driving a steel drift into the yellow-hot head to form the eye into which the handle’s tenon fits. Kosaburo used this same technique to create his eyes, as does Hiroki nowadays, as seen in the video linked to above.

Traditionally this swell was very roughly formed, but Kosaburo carefully hand-filed the swells to be smooth and uniform. I am told by those who know how these things are done that it is much more work to create a pretty swell like this than to quickly grind a head into the modern shape with a uniform waist and flared faces.

From a physics viewpoint, given the same total weight, the modern-style gennou head with its narrower waist and flared faces will have a higher moment of inertia, and will therefore be more resistant to twisting out of alignment during the swing. The flared faces of the modern design also have the advantage of protecting the waist from wear and scratches when the hammer is laid on the ground or on concrete. Most people think the modern design with its flared faces to be a more attractive product. I did too until I purchased my first classic-profile head.

You will of course wonder why Kosaburo bothered to even forge this strange antique-style head. I once asked the same question to an ancient joiner that used this style of gennou head. He was much senior to Mr. Hasegawa, BTW. His answer was three-fold:

First, nostalgia. Remember, he was an old dude back when I was a younger man.

Second, while you may not think so, this shape is more difficult to produce by hand than the modern style, and although it is undeniably “jimi” (地味), meaning plain, or understated, those who know the difference appreciate the subtle details of this design. Very much a wabi sabi thing, one only true craftsmen understand. Remember, ancient dude. I thought he was full of crap at the time. Not anymore.

Third, the swell allows one to use the side of the hammer to drive nails or bang wood in tight spaces. Finish carpenters, joiners and cabinetmakers have this need, as I know from my days in the business. Many Western claw hammers have this ability, but the modern-style gennou head simply doesn’t.

So we have nostalgia, aesthetics, and functionality as factors. As far as I’m concerned, that’s a home run, baby!

This was once the standard profile for gennou heads in Japan, but sometime in the late 1890’s, I am told by people who study these things, and perhaps due to the direct influence of an exceptionally talented master blacksmith named Chiyozuru Korehide, the modern profile head with the flared ends and lacking the swell around the eye became popular.

Any old-fashioned styles that appeal to you?

YMHOS

This image has an empty alt attribute; its file name is 1956-ford-f100
Nostalgic, aesthetically interesting, and functional.
Nostalgic, aesthetically interesting, and functional.

If you have private questions or would like to receive information about our tools, please use the contact form located immediately below. Or you can view this link to our pricelist and photos of this gennou head. Please share your insights and comments with everyone using the form located further below labeled “Leave a Reply.” We aren’t evil Google, incompetent facebook, or thuggish Twitter and so absolutely will not share, sell, or profitably misplace your information. That would be theft. Cross my heart and hope to die.

The Japanese Gennou Hammer & Handle Part 16 – The Drawing Part 5/6

The Christian does not think God will love us because we are good, but that God will make us good because He loves us.

C.S. Lewis

In this post we will continue working on the design drawing of a craftsman’s gennou hammer handle designed and made to specifically fit Gentle Reader’s body and way of working.   

We will layout the top and bottom of the grip area, and include clearance for Gentle Reader’s pinkie finger. The resulting curvature will ensure the striking face will be in proper alignment with either chisel or nail when in use, providing improved accuracy and efficiency, while reducing stresses on joints.

Adding the Top and Bottom Edges

We touched on the shapes of these edges in a previous post, but the time has come to add the lines to our drawing. In a previous post, we extended the two lines in the side view drawing from the eye straight back towards the butt.

With the butt sketched on the drawing with the lowest edge of its downward-facing radius just touching the head’s “striking face plane,” draw an arc the length of your grip from the heel of your palm to the second joint of your index finger, with the compass’s leg pivoting on the intersection of the overall-length line, and top edge of the butt.

Then draw a straight line between the intersection of the OAL line and butt’s upper edge and the top line that you extended from the eye previously. This line will be angled downwards toward the butt.

Next draw a straight line from the intersection of the OAL line over and just touching the pinkie finger circle, until it intersects the bottom line extended from the eye. Combined with your body, and nature of your individual swing, the angle of this line will determine the angle of the head at the point of impact.

Since everyone is different, only you can decide what angle works best for you. These guidelines are a good place to start, but understand you may need to modify or remake the handle until you find the angle that works best for you. By recording the angle in a drawing each time you can adjust it to find the angle that works best for you.

Now smooth out the transition of these lines into a smooth curve, with all edges relieved and radiused, but without making the top edge of the grip area too rounded.

Some people prefer to make these lines and the handle more or less straight, and to change the angle at the point where the handle exits the head’s eye. This is entirely acceptable, but realize such a design depends on really tough wood with interlocked grain or an unusual kink in the grain direction to avoid eventual failure.

I prefer to deal with this change in angle by using a smooth curvature instead. I think it looks better. I know it fits my hand better. It is easier to find wood with a gradual curvature than kinked grain. And my engineering background tells me that I want to avoid sudden transitions that induce stress concentrations, especially where steel meets wood and when grain runout is possible. But it is your decision.

Draw the curves with a pencil, then erase and redraw, erase and redraw until it looks right. 

In the next post we will add the handle’s sides to our drawing.

BTW, links to all the published posts in this series are located below.

YMHOS

If you have questions or would like to learn more about our tools, please see the “Pricelist” link 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, facist facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may the bird of paradise fly up my nose.

Previous Posts in The Japanese Gennou & Handle Series

Clean Wood

Redwoods

Infringe upon the rights of no one. Borrow no tool but what you will return according to promise. Take no wood, nor anything else but what belongs to you – and if you find anything that is not your own, do not hide it away, but report it, that the owner may be found.

Brigham Young

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.

Inspection & Questions

Before we go any further, Gentle Reader, do me a favor. Check the soles of your steel planes. Unless they haven’t been used much, you will probably discover scratches, some of them may even be quite deep. Do you think whatever made these scratches might also have dulled the cutting edges of your planes at the same time?

What could have possibly created these scratches? Have iron pixies been using your planes to shave bricks?

Unless you have a serious pixie infestation, it probably wasn’t anything as large as a brick, but rather tiny particles in or on the wood you have been cutting. Could these vicious, hard particles have grown naturally inside the tree the wood you are using came from? Is there anything that grows naturally inside a tree that is harder than a plane blade’s cutting edge and big enough to cause such deep scratches? Perhaps these abrasive particles were maliciously concealed inside the growing tree by compadres of the shambling horde of 6-armed, green-skinned, Fanta-guzzling aliens that follow me everywhere?

Or could the damage have been caused by nails, screws or staples left in the wood? Perhaps. Pixie toenail clippings? Happens more often than we realize. Tiny fragments of a divorce lawyer’s heart? Maybe, but they are rare and tougher than stellite. No, it’s more likely the culprit is something harder and more insidious than even Murphy’s pointy purple pecker, a substance all around us, one we often ignore.

Nitty Gritty

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 wasted, 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.

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 pervert Murphy been smokin dope and humpin sumpin on your jointer’s bed when you weren’t looking?

Nay, Gentle Reader, supernatural causes aside, and unless you have been grinding legal beagle body parts 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? 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 the cleaning the bathtub: Simply wash it with soap, water and a scrub brush, followed by a rinse.

Bet you never thought of washing wood before have you?

The idea is to wet, scrub 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 hose. A bit of dishwashing soap or borax 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, stand it on stickers on-end, or rest it on-edge, and allow time and circulating air to dry it out of the sun.

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

Disclaimer: It is not well suited for thin material or laminated wood products that might easily warp, 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

First, 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 embedded grit.

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, your tools will thank you over many years with abundant chips, shiny shavings and cheerful little songs. Promise.

Yosemite Valley California, 1865

YMHOS

If you have questions or would like to learn more about our tools, please use the questions 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, incompetent facebook, or thuggish Twitter and so won’t sell, share, or profitably “misplace” your information. If I lie may the bird of paradise fly up my nose.

Gary’s Tool Cabinet

Figure 1: The Chest front view

She walks in beauty, like the night
Of cloudless climes and starry skies;
And all that’s best of dark and bright
Meet in her aspect and her eyes…

Lord Byron

Gary, a truly Beloved Customer, has produced a well-designed and beautifully-executed chest of drawers to be the base of a future larger tool cabinet. The joinery is amazing, and his solutions to the challenges tool cabinets and chests all face are excellent. He was kind enough to put together this guest post for the edification of our Gentle Readers. We hope you enjoy it as much as we did.

YMHOS

Introduction

I’ve been avidly following Stan’s series of posts about tool storage because I’m deep into making my own tool cabinet. After some back and forth with Stan to get his input on some design and hardware options, he asked if I would write a guest post to describe my efforts. I now have completed the chest of drawers, which will be the base for a future upper cabinet. In this post I’ll describe my design decisions and the chest’s unusual construction.

If anyone would like more details, I have a lengthy thread describing the build in even more detail at the Woodworking forum at OWWM.org. (Free registration is required. It is a wonderful site if you are interested in restoring and using vintage woodworking machinery). 

Design Criteria: Functionality

Overall Dimensions

I wanted my tool cabinet to hold the hand tools and other items I use frequently at the bench. It had to fit behind my workbench and in front of a dust collector bin, restrictions that defined the cabinet’s dimensions, which for the chest discussed in this article are roughly 37 inches tall (including the casters) by 18 inches deep, by 32” wide. The upper cabinet will be about 48 inches tall, 60 inches wide with the doors open, and 12 inches deep.

Mobility

This chest had to be mobile because I occasionally need to empty the dust collector bin behind it and access both some closet storage near it and a hatch to the garage attic above it.

Durability & Tool Protection

It also had to be sturdy, durable, modifiable, and repairable. I made modest efforts to protect against dust. I was not concerned about protecting my tools from humidity swings or security since the cabinet will stay in a secure, conditioned space where the relative humidity is between 40% and 60% year round. 

Figure 2: A conceptual sketch of the entire cabinet as it will appear when completed, including the chest of drawers supporting a cabinet with doors, shown where it will reside in my shop,
Figure 3: The completed chest of drawers in its native environment.

Research & Planning

Visually, I wanted the chest to appear, in Stan’s words, “Workmanlike…with some subtle decorative details.” I also wanted it to have a Japanese aesthetic without being a reproduction of a Japanese tansu.

After researching different tool cabinet designs that might fit my criteria — Jim Tolpin’s Toolbox Book was particularly helpful — I started sketching a preliminary design. I decided to combine two kinds of storage: a chest of drawers for smaller items below, and a cabinet with doors above for longer and larger tools.

Initially I drew the chest with full-width drawers to hold larger items, but potential sagging became a concern and I didn’t much like their appearance in my planning sketches. I compromised by having one wide drawer on top and two banks of narrower drawers below supported in the center by a stile.

The upper cabinet design is still in progress. The sketch in Figure 2 above shows planes resting on a slanted surface, but I have decided to store them horizontally to maximize space instead.

One goal I had for the chest was to use mostly interlocking mechanical joints rather than conventional glued/screwed case construction. Joining it mechanically was both an intellectual and design challenge as well as an opportunity to learn new joinery skills. My “tutor” in this effort was Chris Hall, who explored and described this kind of construction in his blog The Carpentry Way, and in several self-published monographs and tutorials. Sadly, Chris passed away in April of 2020. While I am not the craftsman he was, I’m pleased to have a made piece that reflects his approach to woodworking.

 I quickly realized that the build would be complicated enough that using a CAD program would help me draw and visualize the interlocking joints. I took a few weeks to learn enough Sketchup to ensure I didn’t miss any critical dimensions.

Wood Selection

I chose to build the chest from black cherry (Prunus serotina) because this wood is readily available at a reasonable price in my area, is excellent for joinery, and ages nicely.

For the interior I used quarter-sawn sycamore (Platanus occidentalis) because it is relatively hard and stable—and I had recently purchased 100 board feet of it for almost nothing.

I used quarter-sawn Oregon white oak (Quercus garryana) for the drawer sides because it is hard, abrasion resistant, and I can get it locally from a friend whose family runs a sustainable forest and sawmill.

Mobile Base & Joinery

Casters

I considered wheels made from plain iron and with rubber, neoprene, or urethane treads, but selected cast iron, industrial-quality casters for their durability and for the look of iron. I also wanted them to swivel.

I spec’d them to accommodate at least twice the combined weight of the lower chest and upper cabinet when fully loaded.

I decided to use vintage hardware, and I eventually found a set of used Bassick brand cast iron swivel casters with hardened steel carriages, needle roller bearings, and grease fittings. Bassick has been making industrial casters since the late 1800’s. These are probably from the early to mid-1900’s but are still in good shape. I could not find their load rating but similar modern casters have load ratings several times the ultimate weight of the cabinet. They should last a long time. I cleaned them up and attached them with stainless steel screws.

Figure 4: Vintage Bassick model 361 casters

These old casters are noisy rolling over my concrete shop floor, but it’s a noise I like. 

Mobile Base Joinery

I began the construction process with the mobile base. Its key feature is the three-way corner joint shown below. Chris Hall called it a sanpō-zashi Tsugi no Henka (三方差し継手の変化). I followed his step-by-step construction tutorial

Figure 5: Sketchup drawing of the mobile base corner joint

This joint has a mitered corner to hide end grain, an internal sliding dovetail, a half dovetail, a stub tenon, and two locking keys. The larger through mortise is to receive a tenon in the corner post of the chest of drawers that also passes through the chest sill.

The grooves in the upper surface of the mobile base seen in Figures 5 and 8 are to receive loose splines to connect the base to the chest of drawers, and to reduce stresses on the tenons when moving the assembly around the shop. 

Figure 5: The two halves of the three way corner joint

The two keys shown in Figure 8 lock the joint together strongly without glue. The keys cannot work themselves out because they are restrained from above by the corner posts of the the chest of drawers. 

Figure 7: The mobile base corner joint partly assembled
Figure 8: The corner joint with keys inserted but not yet cut flush

The Chest’s Frame

The sill and header are constructed with the same joinery as the mobile base but with slightly different dimensions and other small differences. The sill has grooves cut to accept two plywood dust panels. The header is grooved to accept a solid wood top panel.

Figure 9: Corner post connection to sill showing through tenon with flanking stub tenons.

Center posts help support the drawers. The top drawer is full width. I mortised the posts and stiles to receive tenons on the drawer rails and drawer frames. 

Figure 10: Mobile base, sill, posts, and header.

Drawer Frames and Guides

Figure 11: Quarter-sawn sycamore for rails and drawer guides

The drawer frame sides and guides are quarter-sawn sycamore. Gorgeous, but since these are internal parts, no one will ever see the ray fleck figure unless they remove the drawers and peer inside the chest. I like that. 

The drawer frames that support the drawers have cherry front and back rails and sycamore sides. Front rails for the drawer frames are tenoned into the posts with mitered spear points on the show surface. The spear point is partly structural in that it has a larger bearing surface to resist racking better than a typical plain shoulder. It is also a subtle decorative detail that I  like a lot. It was challenging to get them all to fit. I was more or less successful but not perfect. I included dust panels of ¼ inch birch plywood in the drawer frames to help limit dust in the drawers. This picture is of a test fit before assembly. The blue tape covers drawer stops that are detailed below. 

Fig 12: Chest frame and drawer frames assembly test fit

I tenoned the side rails of the drawer frames into the front rails and also tongue and grooved the side rails into the side guides for extra support for the drawers. Further, the tenons on the front rails also intersect and pass through the tenons on the side guides, locking the side guides in place. The post and side guide “ladder” is extremely rigid to resist racking front to back. 

This complicated joinery is difficult to describe and photograph. Here is a Sketchup view of what the drawer rail and side guides to post connection looks like inside the post. A similar joinery locks the drawer rails and drawer guides at the center posts.

Figure 13: Sketchup X-ray view of rail and side guide to post joinery
Figure 14: Joinery of back drawer frame to center drawer guide and back post
Figure 15: Assembled view of joinery of back drawer frame to center drawer guide and back post.

Drawer Stops

I wanted both cushioned pull-out stops and cushioned push-in stops to prevent accidentally dumping a drawer full of heavy and sharp tools onto the floor or my feet. I also wanted the stops to be replaceable and adjustable for wear over the years.

For the pull-out stops I found a compact design by Australian woodworker Neil Erasmus that I like. These fit into the underside of the front rail and fall into place by gravity when the drawer is pushed in. When you pull the drawer out, the inside of the drawer back hits the leather padded face of the stop. They lift out of the way with a finger if you want to remove the drawer.

I secured these in-place with hide glue so that they can be replaced if they break after a few decades of banging. The leather cushion is from an old belt of mine that has mysteriously shrunk in length over the years.. 

Figure 16: Pull-out stop.
Figure 17: The pull-out stop mortised into a rail

The back stops are my own design. They are dovetailed into the lower surface of the back drawer frame rail. They can be adjusted by adding or removing slivers from the back of the stop, and are easily  replaceable.

I will have to use them for a while to determine if these are a good idea or not. A friend suggested that stops that hit the end grain of the sides would be better than one that hits the center of the more flexible back. I suspect he is right but this is what I have for now and I can re-do the back stop later if I need to. 

Figure 18: Back stop

Side Panels

The chest’s side panels are book matched, hammer veneered cherry on birch plywood cores, friction fit into grooves on the posts to further help resist racking front to back. I added the small, spear pointed rail there to carry the theme seen on the front drawer rails around to the sides and also help resist racking. 

Figure 19: Side panels

The Frame & Panel Back

The back of the chest is frame & panel construction with mitered and through-tenoned corners. The panels are cherry veneer, hammer-veneered with hide glue onto birch plywood cores.

I friction fit the panels into the frames, and friction fit the back into rabbets in the posts to help resist racking from side to side. These veneered panels give the chest a finished look from the back as well as the other three sides.

The weight of the back helps counterbalances the weight of an open drawer.

The eight odd white bits seen in Figure 20 are loose, removable sycamore tenons that pass through mortises in the back frame and down into mortises in the sill, laterally into the posts, and up into the header, attaching the back. One might use screws to accomplish the same thing, but I liked this idea, again from Chris Hall, who adopted it from a Chinese Ming Dynasty cabinet. 

Figure 20: View of Frame & Panel back showing 8 sycamore wood tenons that secure the back panel.

Header

The header frame is grooved to accept a solid wood panel fitted tightly at the front and sides to eliminate any gaps that would collect dust and grit. To accommodate seasonal movement I glued the panel’s front edge into the groove and left a gap at the back, which will be covered by the upper cabinet, so the panel can float.

Figure 21: Header with solid wood panel inset in-place

The odd looking projections seen in Figure 21 are twin sliding dovetail keys that will anchor the future upper cabinet. There will be mating mortises on the underside of the top cabinet. The cabinet will drop onto the keys and slide forward, locking the two pieces together. The upper cabinet will be approximately 12 inches deep, leaving 6 inches of the chest top free. 

Drawers

I put extra work into the drawers since they will actually hold the tools. The rest of the chest is just there to keep the drawers off the floor.

I decided early to avoid metal drawer slides because I find side-mounted slides ugly and believe under-mounted slides sacrifice too much drawer depth. 

Figure 22: A drawer

Drawers fronts are attached with half-blind dovetails, and backs with through- dovetail joints. The cherry drawer fronts are cut from a single clear and straight grained 12/4 board that I resawed to match figure and color vertically and horizontally. 

For the sides I resawed 4/4 oak stock and hand planed it to  ⅜” thick. I chose relatively thin sides both to save material and weight and because I like the look of thinner sides. But they don’t leave much room for a typical ¼” groove for the drawer bottom. To correct for that thinness, I glued on drawer slips of quarter sawn sycamore. Oak would have worked, too.

Drawer slips are, from what I have read, probably a French invention, adopted and most widely used by the British in the 1700’s and 1800’s for finer work but not commonly used in America. Besides providing more “meat” for supporting a groove for the bottom, the slip adds more bearing surface for the drawer. Distributing the drawer weight helps slow the drawer sides from wearing grooves in the runners.

I made the drawer bottoms of sycamore. I slotted the back end of the bottom and screwed to the drawer back to allow seasonal movement.

I’ve also since covered each bottom with a thin sheet of rubberized cork to protect the bottoms from sharp tools and to protect sharp tools from the bottoms. 

Figure 23: A drawer slip

The design of the half-blind dovetail joints was for my own amusement. I wanted a Japanese look for the drawers if possible. A friend sent me a poster of Japanese dovetail styles for inspiration, shown below.

Figure 24: Japanese dovetail poster

I chose the design in the middle at the top with the split pins. They remind me somewhat of Torii gates. 

Torii gates mark sacred ground at Japan's holy sites | MNN - Mother Nature Network
Figure 25: Torii Gate in the sea at Itsukushima Shrine near Hiroshima
Figure 26: Half-lapped dovetails with split pins

This is one of those “subtle decorative details” that is also structurally sound. It actually adds some extra glue surface compared with a standard dovetail, without looking like I was trying too hard just to be different. It also is not visible until the drawer is opened, another hidden feature of the chest that I like. 

Drawer Pulls

The only hardware parts on the chest beside the casters are the drawer pulls. I wanted these to be both durable and aesthetically compatible with the design. 

There are thousands of commercial drawer pull designs and an infinite number if you make your own. To narrow the field, I started by thinking of Japanese tansu hardware. Chris Hall’s website came through with a compendium of styles.

Thinking these had possibilities I started looking for vendors. In the USA, I found three: Hida Tool, which sells iron pulls hand forged in Japan. Eastern Classics, which sells antique iron pulls I think are recycled from defunct tansu. I bought a sample from both suppliers. And Whitechapel, who is superb for European hardware and also had a few tansu pulls but not a large selection of styles and sizes.

Stan recommended I consider pulls made by Nishikawa-Shouten in Japan, which has two large catalogs of traditional and modern tansu hardware. They offer dozens of styles, a few in iron, most in brass, and some in zinc pot metal, with various finishes. It is delightful to look through the catalogs to see what is there. But they are a manufacturer and wholesaler, and their catalog text is in Japanese. After a bit of searching for a retailer I found Morikuni Cabinet Hardware, a Japanese retailer that sells retail — in English — to the US market. Their web store has only a tiny portion of the Nishikawa-Shouten items but they can get others if you ask. 

I settled on a simple traditional Japanese warabi style pull, and also bought samples in iron from Hida Tool and Eastern Classics.  

Figure 27: Eastern Classic’s recycled warabi-style pull

And this more refined contemporary version from Hida Tool, which I liked much better.

Figure 28: Hida Tool’s modern hand forged warabi-style pull

But I needed 14 of them, and neither was available in that quantity. Also, both the Hida Tools and Eastern Classic’s pulls attach with cotter pins, and after consulting with Stan I agreed that the modern pulls with screw-post attachment available from Nishikawa Shouten would be more secure long-term. They also were available in quantity so I purchased a set.

This hardware came with beige/ivory-colored plastic covers to hide the threaded post and its nut inside of the drawer. I liked the low profile and finished look but neither the color nor that it was plastic. I wanted something more durable in metal with a black finish to match the outside. Stan suggested a mirror screw cap, and I found one in brass and stainless steel. I spray painted the caps with a satin black enamel.

Fig 29: Nishikawa-Shouten’s Warabi-style pull with substituted post caps

Finishing Touches

I hate finishing. The scraping, the sanding, the multiple thin coats, the waiting for drying times is maddening. I’m not going to invest in sprayers, either. Not for me. I especially hate sanding. So I go minimalist. I have settled on a couple of simple to apply finishes that are also readily renewable. For my laziness and impatience I sacrifice hardness and durability, but I’m OK with that. 

I hand-planed the exterior surfaces of the chest, then finished it with two coats of 1 pound cut shellac to seal the surface and reduce blotching and then lightly sanded to remove nubs. Then I applied three coats of Waterlox satin, which is an old school tung oil/linseed oil/resin that you wipe on and wipe off. It dries in two or three hours and fully cures in a few days. Refreshing coats can be applied at any time. 

I also hand-planed the drawer frames and guides, lightly sanded them 400 grit, and then just finished them with wax. Before assembly I pre-finished he interior surfaces of the drawers with two coats of shellac and wax. After assembly, I shellacked the outside surfaces. The outside bearing surfaces I then sanded lightly to 400 grit and waxed for smooth running. The drawer fronts also got two coats of Waterlox to match the rest of the outside of the chest. 

Final Comments

Fig 30: Completed chest with drawers open
Fig 31: Drawer with rubberized cork mat and two planes

The chest took me about 2 months to design and about 1000 hours (guessing) for construction. Now I have a proper place to put my tools for the work ahead. 

Gary

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