Sword Forum Bugei

I practice iaido regularly, and i have had a series of issues with my sheath loosening, and my katana no longer locking in its sheath.
I have tried some of the methods in books, and that my teacher have given me, but they seem to no longer work. I would be very great full for some useful advice.

P.S. the reason i haven't got a new sheath is due to the fact, mine is engraved, there for is very important to me.
Also, I bought my katana from bugei about a year ago, it is a crane style.

Well, it would help if we had a few more details, to whit ...

• When did the looseness first exhibit itself?
• What do you mean exactly by "loose"? Is it loose at the koiguchi (and thus the blade slipping free of the saya) or is the koiguchi snug, but the blade rattling around in the saya?
• How loose is loose?
• Is this constant or does it change from day to day? ... hour to hour? ... week to week? ... with the seasons?
• What methods of repair have been suggested and what were the results?

Obviously, having the sword in hand would be ideal for an evaluation, but if the above can be answered, I think we might be able to help a bit more.

It started about 1 month ago.
The Koiguchi will not hug the habaki properly, and thus also causing rattling in the saya, and slipping from the saya.

It is slipping to extent, so that just currying it may become dangerous.
If wile sheathed in the saya, and being worn, may i bend to pick some thing up, it will easily fall out of the saya.

And It has been consistent, despite weather or temperature.

You said "I have tried some of the methods in books, and that my teacher have given me, but they seem to no longer work." What has been tried?

Have you tried shimming the koiguchi? It would be the first thing I would attempt.

Yes i have tried shimming it.

As well as the soaking and drying methiod, And the placing a ruber garmet methiod.

Soaking and drying can be very risky and can damage the saya. In fact, while it can temporarily seem to have fixed the issue, I've seen it cause more harm in the long run than not.

I've also seen the rubber grommet idea and it never works the way it is supposed to according to it's proponents.

That said, I'm not surprised that neither of these worked.

Shimming is a fairly precise process that involves not simply closing up the koiguchi, but reshaping the interior of the koiguchi to more precisely mate up with the habaki not only in the circumference, but also along it's length (or depth, depending on how you wanna look at it.). the end product doesn't simply make the koiguchi smaller/tighter ... it should make it fit more precisely and this can be a bit tricky.

Frankly, I would say that the next step is to get it looked at by someone who has the skill/experience to evaluate the situation, especially given that without seeing it in hand, it's virtually impossible to diagnose the cause and then to advise on a process of rectification.

I've sent you a PM, as well.

Not to sound like a jerk, but your thumb should be on the tsuba whenever the sword is being worn and is not drawn. I know there can be momentary lapses in judgement that cause us to forget, but this is your number one safety measure, not a tightly fitting habaki.

I almost always have my thumb or another finger on the tsuba, holding the sword in the saya, even when I'm not wearing it. The more you practice that, the more it becomes natural. Hopefully you get to the point that it feels unnatural to not be doing it. If you are bending over to do something that requires both hands, it is as easy as taking the sword out of your obi. You can never be too safe when it comes to handling a katana.

Preachy lecture over. I'm sure you already know and practice this. It just bares mention given the topic.

Personally, I think shimming is your best bet and I think Dimytri will be able to help you. FWIW, the koiguchi of my Bugei Samurai and my iaito no longer grips the habaki strong enough to keep it in the saya, so I'm particularly careful to use the "thumb on the tsuba" rule at all times.

If I could jump in here with a quick question about a similar problem; I've found that my Shobu tanto is acting just like the katana's that have been mentioned here. So, while we're on the subject of shimming, could anyone direct me to an explanation of how to shim my saya in order to get a better fit (or explain the process for me, but only if you have the time). I believe that up until now the humidity has been keeping the koiguchi at a perfect fit, but with the frequent changes in the Midwest's weather this is no longer the case.

Much thanks to any help.

What most people do is use a thin self adhesive vaneer strip and put it in the koiguchi on one or both of the sides (where they'll have most contact with the habaki). Usually one is enough, but depending on the thickness it may take more. I'd start on one side, using the thinnest piece I could find and go from there.

I had a polisher shim my saya for me once without my asking. He shimmed the saya on the edge side. Just a little strip. Unfortunately, during the trip back home the habaki closed down all the way and caused the saya to crack because of this shim. I didn't even notice it until I was trying to figure out why it cracked.

A couple key points to remember: It's easier to add material than it is to remove it (in the context of shimming). Take your time and don't force anything.