Sword Making “Taiken”

Sword Making “Taiken”
By Yulin Zhuang

How much of a five-year apprenticeship can you distill into a single day of training? That was a question that three of us, (David Groff – who recently published a new translation of the Gorin no Sho, KW’s general manager Baptiste Tavernier, and votre serviteur) decided to put to the test when we went to make our own kozuka, a small knife traditionally inserted in the side of the saya.

When I think of a Japanese swordsmith’s house, I typically imagine a small cottage in the middle of a rural area, perhaps surrounded by farmland. Thus it was a bit of a surprise when we pulled up to a nondescript house in a typical urban Tokyo neighborhood. The three of us were greeted by an equal sized party—the master, his disciple, and an older apprentice. It is the disciple, a frail-looking young man with six years of experience behind him, that will be teaching us today. He is not how you would picture a swordsmith either. He’s thin, wiry, and somewhat gawky.

The interior of the workshop is dark, cramped, and overwhelmingly grey—the color of ash, charcoal, concrete, and unpolished metal. The only spots of color are a slight orange patina of rust on the unfinished swords stacked carelessly against the wall or in old paint buckets. Despite being high-ceilinged, there are only two windows near the forge, both small and close to the ground, contributing to the overall gloom.
Normally, the process to make even something as small as a kozuka would take a few days from start to finish. To finish in just a day, we had to cut out a few steps—thus we started with a brief demonstration of the process of attaching the block of steel to a long iron bar, to facilitate the hammering process.

We started by learning how to operate the wooden bellows, trying to reproduce the distinctive clack-roar as it operates. Japanese bellows use a unique design that blows air from below into the forge both on the pushing and on the pulling motion. With each push and pull, we could visibly see the flames leap high and hear the charcoal crackle.

DSCF9566David operating the bellow

When the metal is heated to the correct temperature, it gives off the distinct crackling noise of rice crispies in milk. When pulled out from under the charcoal, it hisses and spits glowing embers everywhere like a fireworks sparkler. The next steps must be performed quickly, before the metal can cool—it’s removed with tongs, inverted, struck with a file to remove slag, a spoonful of a mysterious white powder is added, then the iron bar is removed, struck, and then hammered together. It sounds simple, but when confronted with that furiously sparking block of red-hot metal, it’s easy to freeze.

DSCF9577Me, tamahagane and sparkles

It’s an odd sensation to have glowing steel in your hand that is sticky, like someone left a wad of bubble-gum. Even odder to be hitting something that sparks with each strike.

At this point, the laborious process of hammering and folding the steel to shape the blade would begin. Unfortunately, since this alone takes quite a few hours, we had to skip it and start with a few pre-shaped blanks.

Using a coarse rasp, we began to file the steel blank, to flatten the surface and prepare it for carving. This involved a great deal of trying to find the optimum geometry to hold it firmly while still being able to file with a completely flat stroke. Our guide wryly remarked, “kore ha seikaku ga deru tokoro”, or “this step is where people’s personality comes out”. It certain brought out the streak of perfectionism in all of us. We would hold the blade up to the light constantly (to give our cramping fingers a break) and anxiously ask our teachers “is this good enough?” “Yes, that looks good!” To which, we would smile…and then go back to filing again, just to get it a little more perfect.

A brief note here—as you can see from the picture, this kozuka is actually not straight. In fact, it curves towards the front of the blade, the reverse of what we normally see in a finished sword. This is due to the quenching process, where differential cooling causes the metal to warp. Smiths must compensate for this warping in the forging process, in order to create a straight blade.


After a brief break for lunch, our afternoon began with metal carving. We were given small chisels, a brief demonstration, and left to practice on some scrap metal. It was left up to us to decide what we wanted to write.

Chiseling metal is an art form. We were supposed to use the corner of the chisel, and make a series of triangular indentations.  The hardness of the steel makes it difficult to make an impression, so the chisel is apt to slide around. After trying to carve just the character for my last name a few times, I quickly revised my plan. At the best of times, my kanji look like a first grader’s early attempts, and this merely accentuated the poorness. Being an immense nerd, I quickly switched to carving my initials in Lord of the Rings dwarven runes (the Angerthas Daeron, for the extra geeky). I figured since runes were originally made to be cut in stone, they must be easier to carve into hard objects.

Baptiste, being the more ambitious among us, decided to go with some complex geometric kanji. David opted for an abstract design of his initials. After painting on the characters for reference, we went to try to make our designs a reality.

DSCF9679Baptiste chiseling his kozuka… scary… …

Unfortunately for me, the steel was both harder than our scrap practice metal, and also not flat—it angles from back to blade. This resulted in none of my lines being parallel to each other, and most of them not being straight. Baptiste had much better luck with his.

DSCF9681B‘s note : “luck? No dude, this is waza

This gave me a whole new appreciation for the difficulty of dragon carvings or other designs we often see on sword blades. We couldn’t even chisel two straight lines, and so the artistry required for chiseling a dragon boggles the mind.

After scrubbing off the blade with ash and water to remove any lingering oils from our hands, we moved outside to place on the clay. The distinctive hamon line, marking the harder steel of the blade edge and the softer steel of the back is created through the careful application of a special clay mix. By varying the thickness of the clay, it varies the speed the metal cools when quenched, helping to create that difference.
Creating the fancy hamon patterns is harder than it sounds—our teacher confessed to me that even after 6 years of practice, he still couldn’t fully predict what kind of hamon he would get.

Imagine a popsicle under the summer sun, the watery-at-the-edges-yet-viscous fluid that is threatening to fall off the wooden stick. Now imagine trying to spread that ice cream in a thick-yet-even layer across the popsicle stick.


The clay slurry is mixed up on what looks remarkably like a Coldstone Creamery counter, using two long thin spatulas, in a motion much like what they use when putting in toppings. The ingredients, however, are far less delicious—some clay, some finely ground stone, charcoal, and some other ingredients to match. The recipe varies from smith to smith.

Luckily, the smiths had a few tricks to help, and we quickly finished and set aside our blades to dry, a process speeded up by suspending them over a bed of coals like grilled fish on a stick. Next to come: the true test of fire, literally.

Yaki-ire is the final step of making the sword, and the most critical. It is this step that raises the Japanese sword to its peerless quality, or reduces it to a chunk of scrap metal. The charcoal used for this is smaller and finer, leading to a less high temperature. An electric fan is used to blow air into the forge, a small concession to modern technology that allows the smith to focus on the blade in the flames. In a Japanese forge, the hot spot is quite small, and thus the smith must constantly shift the blade in the fire to ensure even heating.

The time has come. An anticipatory hush descends over our group. The master swordsmith, hitherto mostly a benign presence outside the forge chatting with our guide, takes up an arms-crossed stance in the back. As our first volunteer steps forward, the reason for the small windows becomes apparent—they are quickly shut and the lights turned out, leaving us bathed only in the warm glow from the forge. It is traditional that the yaki-ire process is done in darkness, leaving the smith to judge the correct temperature of the blade through the color it glows alone.

I’m the last to go, taking a seat next to the forge and picking up my blade with the tongs. The heat from the forge is incredible, but I’m buttoned up tight with long sleeves and gloves to protect me from sparks. However, as I place the blade in its bed of coals, I’m hardly aware of the heat. I’m lost, bemused by the leaping flames and roar of the fire. For now, there’s only me, the darkness, and the fire. I’m so enthralled, in fact, that I forget that I’m supposed to be counting down the seconds, and hastily shift the blade to even the heat. One one thousand, two one thousand, three one thousand…


At the end of my countdown, I lift the blade out of the flames and hold it suspended above the water trough for a brief instant, long enough for the smith to signal that the temperature is right, and then firmly douse it into the warm water.

The windows are quickly reopened and the lights turned back on, letting a welcome breath of cool air into the forge and breaking the spell. The blade is given a quick polish, and I’m congratulated. Apparently I’ve done well, the hamon is easily visible, and the blade seems fine. Apparently we’ve all done surprisingly well, setting some new kind of record for beginners. I have nothing to say to this, other than a plaintive “but I didn’t do anything, just followed instructions…”

The blade is returned to the flames once more, for yaki-modoshi, a final step that helps soften the too-hard temper of the blade. It seems almost anticlimactic at this point, like a drawn out epilogue.
We’re given a chance to admire our work a bit, and then wrap up. Our blades are now off to the next set of craftsmen—the polisher, the habaki maker, and the saya maker. We won’t get to see our finished product for many months yet.

DSCF9731Ready for polishing!

So will this experience make me a better budoka?

Probably not. I’d love to say yes, and wax poetic about the new insights I have into the heart of the sword—the soul of the samurai—but alas, such bolts of inspiration have yet to come. Perhaps they will when I finally get my hands on the kozuka. Nevertheless, it has given me a new appreciation for the art of the Japanese sword. Not just a skill, but truly an art, drawn with steel and fire instead of ink and paper. It was my deep honor to be given this opportunity, and it is a memory I will treasure for the rest of my life.