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jezah81
9th November 2006, 04:26
Hi guys,

I was talking to my friend the other day and he brought up something that was interesting to me. His sensei once told him that mekugi shouldnt be in too "tight" or loose either. Has anyone else heard of this?? How can you tell if its too tight??

Kind Regards,

Jeremy Hagop

Ken-Hawaii
10th November 2006, 00:34
I guess the obvious answer is whether the blade falls out of the tsuka (on the too-loose end) & whether the mekugi requires a jackhammer to remove (other end) :p . I use a homemade hole-punch & special hammer (small brass head) to remove & replace the mekugi in my iaito.

I change my tsuba fairly frequently, Jeremy, & have had to replace my mekugi only once in quite a few years. And that was my fault because I wasn't paying enough attention when I tapped it back in, & the wood kinda' spread out like a mushroom head. I've found that I can easily notice when the mekugi isn't perfectly/solidly in place because the blade has a tendency to move slightly when I swing (I do 1,000 suburi each day, so any changes are noticed in a few swings).

Not sure what that sensei meant, though :confused:.

kdlarman
10th November 2006, 02:24
Ken, you might consider changing them more often.

FWIW if you want a *really* good source for very good mekugi go to a local craft store. You should have no problem finding bamboo knitting needles from Japan given you're in Hawaii. They use the same type of aged bamboo to make those knitting needles and even use the same section of the bamboo that koshirae makers use when making mekugi. And heck, you can get them "pre-shaped" for the most part because they offer the knitting needles in various sizes. Just gently taper it with a file to fit your ana and trim the excess.

Just a fwiw.

And Jeremy, I have no idea what your friend meant. Why don't you ask him instead? Mekugi shouldn't fall out easily. Tight is good. If you can't get it out you can't check it, but the only time that has ever been a problem for me was with mekugi made of poor materials or very, very old mekugi that were locked in with crud in an antique.

Ken-Hawaii
10th November 2006, 02:43
Wow! That's a great idea! I've been grabbing a chunk of bamboo from my backyard (we grow it for tameshigiri) & just carving/shaping my own. I always have a couple pre-carved so they have time to age & shrink. But you're right that I've seen quite a few bamboo knitting needles (or whatever the heck they use them for) in many local stores.

I'm curious why I should change out my mekugi more frequently, though. If it's not broken, fits well, etc., what's the purpose in changing it out?

kdlarman
10th November 2006, 03:19
Over time the bamboo dries and gets a bit more likely to disintegrate. Also, constant use will tend to slightly deform the mekugi allowing slightly more movement in the nakago especially where it is "pressing" against the back of the mekugi-ana of the nakago. If the nakago has very slight movement (even if it is to the point that you may not feel it yet) the nakago can start to deform the nakago channel ever so slightly. That means that it will start to be noticably loose sooner than it otherwise might and it will that much harder to get it snug again. Finally, the mekugi, even if it doesn't get deformed, will sometimes tend to cause the mekugi ana itself to deform slightly, essentially enlarging the ana itself in the tsuka core. The pressure of the constant cutting can cause that ana to "grow" oh-so-slightly. So a new, tighter and very slightly larger mekugi will snug things back up before anything can become problematic. This will also address slight looseness that occurs as the tsuka core naturally shrinks slightly over time as it causes the nakago to seat slightly deeper into the tsuka.

Finally... Why not? Better safe than sorry.

Bottom line is that it addresses a series of problems that are very minor. But in combination they are part of the reason a tsuka will develop slop a year earlier than another. So you might gain an extra year or two of use out of the tsuka.

And it is simply a good habit to have and a good skill to develop.

Incidentally the "good" bamboo is a very specific type and aged in a very specific way. The knitting needles are fantastic. You can also buy chunks of susudake directly from suppliers like Namikawa Heibei in Japan if you want to carve your own. I have that for my customers who are *very* serious about traditional materials only. For everyone else who wants bamboo I use the knitting needles. For everyone else beyond that I use black delrin mekugi I have tapered on a lathe to very precise tolerance all while I use a very precise machinists tapered reamer to shape the ana in the tsuka for a perfect fit.

Lots of solutions to various problems... ;)

rottunpunk
10th November 2006, 10:12
i use bits of bamboo chopsticks for my mekugi
:p

jezah81
10th November 2006, 12:31
Thanks for your answers guys. By the way Keith, how often should mekugi be replaced in your opinion?? Considering kata once a week and cutting every two weeks with the sword??

Kind Regards,

Jeremy Hagop

kdlarman
10th November 2006, 15:17
i use bits of bamboo chopsticks for my mekugi
:pGiven the emoticon I'll assume you're joking...