Tsuka problem

[jezah81]

Hi guys,

 

I just received a tsuka that i had re-wrapped from Japan. Everything is nice and tight, and aesthetically pleasing, BUT the damn thing wont fit back onto the nakago. Before I sent the tsuka to Japan, it was fitting fine onto the nakago, not loose, but not extaordinarily tight either. Now the nakago will not go all the way into the tsuka, there is about 1 inch of the nakago that refuses to go in. Is there any way to fix this problem myself? Has anyone else ever experienced this or heard of it before? What are the reasons for this?

 

Kind Regards,

 

Jeremy Hagop

[andreas]

Hi,

let it dry few weeks. I had once that same problem, but ileave it for couple months and now it fits like a ....

[Nobody]

Hi,

 

IMHO, the space for the nakago seems to have become narrower because of the tension of ito which are newly wrapped.

I heard that the space in a tsuka is made rather loose to take the tension of ito into account.

[Brian]

Agreed with Moriyama san. I have seen this often with good re-wraps. Those things are wrapped tight and will compress the tsuka so that the nakago won't fit in again.

I would suggest contacting Keith Larman here: http://www.swordforumbugei.com/phpBB2/viewforum.php?f=2 or Ted Tenold at http://www.legacyswords.com/newindex.htm

They should be able to advise you on how to proceed. I wouldn't force it for fear of cracking the wood, and I am not sure how much it will open up again on its own over time.

 

Brian

[Keith Larman]

Hey, Brian, thanks...

 

FWIW there are multiple things at play most likely. How many of you guys in drier climates get swords from Japan in Shirasaya only to find the fit too tight a month or two later? To the point of even splitting the saya sometimes? Welcome to the world of climate differences. Wood likes to expand and contract (swell/shrink) depending on heat and humidity.

 

Next add to the equation a quality tsukamaki job. As already mentnioned that can compress things further and make them even tighter. FWIW when I'm making a new tsuka (especially for a practitioner) I start off with a snug shitaji. Not super tight, but consistenly snug. No rattle but not "use a hammer" to get it off tight. By the time a full wrap samekawa has been tightly bound and dried, well it gets tighter. When I'm waiting for the glue to dry on the same on the core I'll often gently tape the tsuka core onto the nakago to help keep the interior shape intact just in case. Next once the tsukamaki is done it often won't seat anywhere nearly as easily as when it was just the core. I get it on the nakago asap to make sure it settles into its new, compressed, tight state.

 

And this can be a problem, especially if you have a soft metal/nice/fragile kashira. It isn't just that whacking it with a soft mallet might damage the detail of the surface, you can often fairly easily "taco" the kashira. Sometimes when you see a kashira where the ha and mune sides seem "flared up" a bit and the center of the face of the kashira looks "funny" for lack of a better term, that usually means the sword was either dropped directly on the kashira *or* someone whacked it and deformed the kashira on the core itself.

 

This is a real possibility with shallow kashira as the ana for the ito is close to the face. That means you "slot" the end of the tsuka shitaji rather than drilling through. This means there is no wood core inside supporting the face but wood on the ha and mune. So you whack with the mallet, even gently, and voila, you've just reshaped your kashira...

 

Assuming this is a new core that you had rewrapped: My advice is to slide up as far as possible on the nakago. Gently whack it with your palm a few times at the kashira to move it as much as you can without causing massive bruising. Then let it rest a day or so. You're letting the wood fibers in that section compress a bit and "set" into place. The best time to do this is on a warmer, wet day if possible. that causes the wood to swell and expand making it easier to get it together. Regardless, wait a day or two, remove the tsuka gently and carefully then immediatley try to put it back on again. Whack it some more with your palm since you're not likely to damage the kashira with that. Refresh that bruise on your palm. Hopefully the tsuka will push up a bit further. Be patient, it may take weeks but you can possibly get it back onto the nakago.

 

If this is an antique core or if the above doesn't work... You need to have someone who knows what they're doing rasp out the interior with a tsuka file and get it fit. That takes some experience and sensitivity to where things tend to bind. They will need the entire sword, obviously.

 

Finally... As an observation... I rarely take on rewrap jobs unless the customer will leave the entire sword. And I often refuse to do rewraps on other people's craftwork unless I know their work. Too many variables. A good wrap should be tight. Tight can adjust the fit. And getting it back on the nakago *right away* is the best time to do it. And if it is too tight then they have everything they need to adjust the fit and get it right. So it is always best to have everything together when doing that kind of work.

 

If you're talking about an ancient tsuka it usually doesn't really matter. Most of the times you may tension the ito quite so much if you're concerned about cracking old wood. And they're usually pretty loose at that point to begin with.

 

Just my experiences doing both new and rewrapped old tsuka for both old blades and new. FWIW.

[jezah81]

Thanks for your answers guys, especially to you Keith. I spoke to my contact in Japan who got his tsukamakishi to do the re-wrap,(for a newly made tsuka made of honoki). His advice was to cover the kashira with a thick piece of cloth and gently tap the tsuka back into place with a rubber mallet. After 30 minutes of doing just that, I was finally able to get the tsuka back on with no problem. My friend in Japan also mentioned that it is common in Japan for tsuka to be so tight, especially on user blades. The registration office where swords are registered in Japan apparently keep many mallets and buffers for this reason. Better to have a tight tsuka than a loose one i suppose.....

 

Kind Regards,

 

Jeremy Hagop

[Darcy]

Just to give an idea how much wood moves with climate...

 

I shipped a sword out once where the new owner let me know that the tsuka was so tight he could not remove it.

 

Two weeks later his new worry was that it was falling off because it was so loose.

 

I built a table for my kitchen with a poor design... combined wood grain running 90 degrees from each other. The movement of the wood just with changing winter to summer caused several sixteenth and one eighth inch gaps to open up in the tabletop.

 

Wood is a very dynamic material, especially unfinished wood as is used with swords. Whenever you ship it from one location to another you will have movement (i.e. changes in dimensions). The wood will change much less along the grain than the cross section which will expand and contract often dramatically with humidity, elevation, temperature.

[Carlo Giuseppe Tacchini]

Even a new cut in an extremely seasoned wood can result in an

"awakening" of the fibers. I've made a bench from a

centuries-old roof beam of Quercus Robur removed from a roof that had to be altered.

Nothwithstanding it needed several bend-saw blades to be cut into planks and it is repaired by rain under the new patio, untreatened, it clearly showed adjustments after some months. Millimeters, but still there...