PDA

View Full Version : Strange iaito problem



Ken-Hawaii
29th June 2015, 06:06
I've trained in MJER for many years, & am now having a very weird problem with my iaito. Both this blade & my last one are aluminum-beryllium, & about 2.4-shaku. On one side of the mune - only - there are developing a string of what look like chips, but are actually small, evenly-spaced openings in the burnished metal. I had to retire my last blade because of the damage it did to my hand during noto, especially in Okuden waza, & now this fairly new blade, less than 3 years old, is developing exactly the same problem. Both Sensei & I have looked at it, & neither of us has a clue as to why it's happening.

Under magnification, it almost looks like gremlins have chipped away at the mune's surface on the one side, but the other side is perfectly smooth. I've eliminated things like a defect in the koiguchi or inside the saya, but other than that, I don't have a clue why my blades are essentially retiring themselves. Both are fairly customized, & although I could of course go to steel, I really don't want to put any more strain on my rebuilt shoulder.

Has anyone else experienced this, or have any idea what may be causing it?

Thanks!
Ken

Brian Owens
29th June 2015, 06:36
I would have suspected pitting from exposure to salt (sweat, sea breeze, etc.), but the "evenly spaced" part would seemingly rule that out. Very curious!

Ken-Hawaii
29th June 2015, 07:00
Yeah, Brian, my wife & I are both engineers, but still don't have a clue what's happening. If both sides of the mune were pitting, I could at least understand it, but just one? My wife's blade, bought from the same place at the same time, is just fine, BTW.

It's not that I can't afford to replace a blade, but really don't WANT to!

Ken

hyaku
29th June 2015, 07:07
Yeah, Brian, my wife & I are both engineers, but still don't have a clue what's happening. If both sides of the mune were pitting, I could at least understand it, but just one? My wife's blade, bought from the same place at the same time, is just fine, BTW.

It's not that I can't afford to replace a blade, but really don't WANT to!

Ken

Sounds like the plating is very thin. What do you use to clean it Ken?

Ken-Hawaii
29th June 2015, 07:17
A soft piece of toweling with some oil, pretty much the same thing I use to clean my Nihonto.

Ken

pgsmith
29th June 2015, 19:19
If I had to guess, I would say that there was some contamination on either the aluminum alloy core when they applied the copper plating, or on the copper when they applied the chrome plating. Have you tried talking to the company that made the sword? They may offer at least a discount on a replacement blade.
I've seen several iaito that have developed problems with the chrome plating not adhering properly, and it always seems to be somewhere around the kissaki.

Ken-Hawaii
29th June 2015, 23:29
Linda & I also assume the contamination, Paul, but these were blades from two different companies, one I had custom-made in Tokyo, & the other earlier blade from Tozando, with exactly the same problem. Just doesn't make any sense! I did send photos to Tozando, who told me that they'd never seen this happen before, & suggested I go to a steel blade.

I'm hoping that I can find one or two more people with the same problem so that I can start looking for commonalities. Frustrating!

Ken

Brian Owens
30th June 2015, 09:18
Ken, are you able to wear watches without any problems?

Ken-Hawaii
30th June 2015, 09:38
Ha! Yes, Brian, although the one I usually wear is 18 kt. But I have a plain old steel band on another watch I wear often enough that I'd notice any sign of corrosion. And I have the advantage of being a chemical engineer myself, & my wife is a chemist.

Again, if the problem was on BOTH sides of the mune, I'd have a lot more to work with!

Ken