Iaito Reborn As A Wakizashi Part 2

Okay, so last week, I cut a new nakago (tang) in the broken blade, made some fittings with Art Clay Silver, and got started carving out the saya (sheath).  Seeing how I still have ten each of fingers and toes, and not covered in third degree burns, I've assessed myself as mentally and physically fit to continue with the project.

Now repeat the inletting for the blade on the other half of the saya. For a proper saya, the only part of the blade that should touch the inside of the saya is the mune (unsharp edge at back of blade). The tight fit of the habaki (that collar thingy that helps snug the blade onto the scabbard) takes care of the rest.

Before you glue the halves together, check to make sure the blade has this proper clearance, and that it can slide in and out of the saya without obstruction.

 

I used Gorilla Wood Glue for the saya because rice, although the traditional choice, is for eating, not gluing.  Especially when you grew up in an Asian family.  C-clamps come in handy (can be bought at a dollar store if you're really poor), but you should also consider one of those ratcheting clamps to the right, because you will really need it for the tsukamaki (hilt wrapping) later on unless you're using leather (more on that later).

You should sandwich your saya halves between two pieces of scrap wood to avoid turning the surface into a moonscape with the C-clamps.  Unless that's the effect you're going for.

 

To shape the saya, I highly recommend a traditional Japanese plane called a kanna, although a Western plane works fine as well.

Kannas are rather low-tech (you only need to tap with a hammer to adjust), and require a different technique from a Western plane (you pull rather than push). However, you only need to extend the blade less than half a mm and that thing planes through wood like melted butter. This is something you expect from a country known for really sharp things.

You can get a kanna next time you go to Japan at Tokyu Hands, or online. 

 

Now for the finishing touches before lacquering.

If you find that your plane got a little "greedy" and shaved off too much wood, try rebuilding the lost portion with epoxy and careful use of a wooden Starbucks stir stick. If you feel bad about taking stir sticks from Starbucks, put them back in the condiment station once you're done with them.

Sand the surface until it is nice and even, as little nicks, dents and corners will still show through the lacquer. Since water buffalo horn is impossible to buy here, and what little I managed to get off of eBay is reserved for the koiguchi (cap at the sheath opening), I fashioned a kurikata (knob on the side of the sheath where the cord threads through) out of a scrap piece of wood.

I also recommend a kojiri (end cap on the saya), since the end of the saya can get pretty dinged up. The metal ones are the best, but they are tricky to find and can be a bit pricey, so you can use horn. If you encounter the aforementioned scarcity, then you could probably make an endcap with whatever durable material you can find (or even...epoxy!).  Or just make do with none at all.

And in case you're wondering, I glued on the kojiri before lacquering to ensure its edge seamlessly blends into the saya.

 

Normally, this is also the time to install the koiguchi. Normally, the koiguchi should "wrap" around the opening of the saya.

In my case, my homemade habaki was so thick and the saya opening so wide that there's no room for the koiguchi, so I had to glue the koiguchi on top of the saya opening rather than around it. Because of my procedural deviations, these steps for me were performed near the end when the saya was almost complete, but I'll put them here in the "normal" order.

In retrospect, I should've installed the koiguchi at this point as well so that the lacquer would have blended seamlessly.

For the normal method, you'll need to first carve a place for the koiguchi around the saya opening. (You'll have to Google for images and diagrams.)

Hopefully you are able to procure a buffalo horn blank from eBay or somewhere.

Start by tracing out the the end of the saya on a piece of paper. Cut out the outline and affix on the buffalo horn with rubber cement or two-sided tape so you can peel it off later.

It would be simpler to just trace out the saya directly on the horn with a sharpie, but good luck seeing what you just traced.

First cut as much as you can with a hacksaw, such as the corners, to save you some work, but don't cut too close.

 

Use a Dremel to sand the horn to shape (or file if you are Dremelless).

For safety and grip, be sure to wear nitrile-coated work gloves. Unless you like retrieving your work across the room with bloody stumps where your fingertips used to be.

Fit the shape of the horn to the end of the saya.

But before you begin, here's a little brain exercise... What is buffalo horn made of? Keratin! What is hair made of? Keratin! What does it smell like when you subject buffalo horn to lots of friction and heat??!?  Open the window.

 

Once the outline of the horn is to your satisfaction, drill some holes in the middle of the horn to start off the opening.

If you have it, a multipurpose bit (#561) on the Dremel will literally shave off a lot of work. They can also shave off a lot of your fingers too, so for the love of God, keep those freakin' gloves on!!!  Trust me.  Better yet, use a clamp to hold the horn.

Fine tune the koiguchi opening with files, fitting it not only to the saya but to the habaki of the blade. If you are making the koiguchi my way rather than the normal way, the koiguchi must fit loosely over the habaki; all the tension will be taken up by the wooden part of the saya opening.

Once it is the right fit, bevel the inner edge of the koiguchi opening. Then, smoothen the outer edges with progressively finer grits of sandpaper. Finally, smoothen all edges with the finest grade (#0000) of steel wool. You'll need to polish further if you want the koiguchi to be nice and shiny.

Once the koiguchi is complete, glue it to the end of the saya.

 

You should start on the next couple of steps right away before starting work on the tsuka (hilt), as they are time-consuming and best performed concurrently with tsuka work if you don't want your project timeline to be needlessly delayed.

Traditional Japanese lacquer (urushi) is very hard to come by and it is also toxic, coming from a tree that wants to kill you.  Since I can't trust myself no to lick my fingers after every coat, I though a can of spray-on lacquer from Home Despot would do the trick.

Big mistake.

The coats took forever to really not dry, and I ended up with a gummy non-Newtonian mess that I had to strip and start over.  Instead, I found acrylic enamel to be vastly superior.  At this point, this project has already vastly departed from traditional and I don't have time to go to Japan for a 20-year apprenticeship.

If you get any runs, exercise damage control by carefully dabbing it out with a paper towel before it forms large sticky beads that take forever to dry and are a huge pain in the ass to sand off.

Once the coat has thoroughly dried, buff down any runs or run remnants with VERY FINE sandpaper (no less than 400 grit, I'd say), and wipe down with a damp cloth/paper towel to get the dust off before applying the next coat.

If it's really windy outside, you're better off postponing the coat rather than risk runs and beading because your spray is blown all over the place.

 

The other step is to pre-stretch the tsukaito (hilt wrap) for several days to prevent it from loosening after it has wrapped your tsuka.

For me, I'm a huge fan of tsukaito (and other things) made of leather, which is prone to getting loose if not stretched out. Unlike cotton or silk, leather doesn't get unwashably dirty or gummy, yet still retains a good grip.

So unless you actually do want to enhance your grip with a slurry of dead skin cells, ripe sebaceous secretions, and aged perspiration, leather is the way to go if you can find/afford it.

I used eBay for mine, but I don't recommend the cheaper synthetic vinyl (hold a Paul Chen Practical Plus Katana to see what it feels like).

At least for leather, I do NOT recommend more than 1.5L of water for weight. Sadly, this threshold was derived empirically, when my tsukaito snapped and became a huge pain in the ass to repair.

For this, you can either use a STURDY shower curtain bar, or one of those door chin-up bars you buy on your annual New Year resolution to lose weight but will never use for any actual exercise.

 

Now you can proceed to the tsuka. It's the same deal as the saya, except now you have to be careful about achieving a precisely tight fit. Just DON'T FORGET to put the habaki, tsuba (hanguard), and seppas (spacers) on before you trace it out.  Since you can't fit the fuchi (collar around hilt near the hanguard) at this point, you can try to factor it in, but if you can't it won't be an issue.

If you thought the saya was a pain, chiseling out the tsuka can be a tedious exercise of trial and error, and you may have to further shape the nakago with the file as you go along. Just be glad that the nakago isn't as long as the blade.

Be extra careful when you work the edges first, and if you find you've chiseled out too much, try filling it back in using epoxy shaped by a strip of masking tape.

And yes, I know my Toothless pencil is awesome and no, you may not have it.

 

That's it for this week's project installment.  Stay tuned next week when we delve more into the tsuka and how to wrap the same (rayskin). 

On to Part 3