Tsuka-Ito Wrapping

[ROKUJURO]

Any blade smith, metalworker or mechanic should be able to make a jig on specification. MEKUGI is not really necessary if the jig fits the TSUKA nicely. 

[ggil]

Mr. Buck’s

Book shows how to make a jig out of plywood, and a piece of A blade that includes the nakago, I got a cheap wall hanger to chop down for that purpose. Pretty cheap and easy.

 

 

Hashigami help here: (this person tested various materials and found a really strong Japanese mulberry paper and dyes them - awesome!) http://www.cottontailcustoms.com/hishigami/

[Ryubiken]

I use a fabricated piece of "nakago shaped" metal bar in my jig. Problem with cut off piece of existing blade is that they all have different dimensions (Except for Iaito-blades). You would need many different types of nakago, or one that is so small and short that it fits all. Instead making slim, tapering and round cornered steel bar enables you to get tight enough fit when wrapping tsuka-ito. When wrapping the ito, using hishigami is must if good result is desired. Especially when making folds over menuki. Without the hishigami the the higher the menuki the more wider "diamonds" you get.

 

Also as said earlier, oak is a bad choice for tsuka material. It affects nakago patination and might expose it to rust. Also in practical point of view, oak is so hard that it can't handle the stress of using the blade, plus it's pain in the kojiri to work with. This is of course not a concern on 99% of blades which are preserved and displayed.

 

When making tsuka core the most important factor is absolute fit inside. I use very very soft graphite powder dusted on the nakago. When clamping the two tsuka halves together and sliding the nakago in you can see where the nakago "floats" on the wood. When removing those parts, you get closer and closer to good fit. The fit has to be on all 4 "walls" and on the whole length of the tsuka.

 

If nakago has any gap or movement inside the tsuka, it's not safe to handle, since effectively the only thing keeping the two halves together is rice glue and in some extent tsuka-itos pressure (Only in new wraps, old one's tend to get loose). Fuchi and kashira have very little in the ways of preventing separation of tsuka. Fuchi should be "snap tight", but not glued. It's purpose is to give flat, straight and hard surface against the seppa for tightening (plai wood surface would compress too easily), not to reinforce the tsuka. On some Japanese made koshirae I have seen kashira that have been glued with sap-like substance.

 

Samegawa on the other hand can give huge improvement on rigidity. If full-wrap is made correctly, it can keep the tsuka together almost by itself. Panel style doesn't of course have this advantage.

 

Photos for attention

[Brian]

Good write-up!

[raynor]

Hi,

 

Apologies if this is off topic, but does anyone have any sure ways to tell a rayon wrap from a silk wrap without literally lighting it on fire?

[ROKUJURO]

Omar,

you could but normally you do not want to set the whole thing on fire!  Just let the flame come near a very small end of it. 

[Ryubiken]

Silk feels slightly warm when squeezing it tightly for a while. Rayon on the other hand feels more like cold plastic. Also if you scuff the surface you notice that cotton and silk tend to peel or get rough and torn into fabricy surface (small "hairs" are coming off). Both also feel soft.

 

Rayon on the otherhand makes more rough and rattling sound and you get more cleaner and harder peel. Rayon feels hard compared to silk or cotton.

 

It's hard to explain in text, but when you see different ito materials on hand it's really obvious to tell the difference.

 

Generally ito made of rayon is also larger in structure, meaning the single lines of which the weave is made are thicker.

 

Worst part of rayon is that when doing tsukamaki or training with, they actually give you burns on your hands. Cotton is more forgiving and silk is of course the most gentle.

[Ryubiken]

Also rayon is glossy (like your sword on another thread). Silk and cotton are matte in nature. Although they get a bit glossy over time, but it takes lots of use and sweaty hands. Still not as glossy as rayon, which on the contrary loses it's gloss when used.

[ggil]

Kimmo,

 

Thanks for the excellent contribution!