Adrian Posted March 27, 2013 Report Posted March 27, 2013 Obviously the space in the seppas and the tsuba needs to be a bit longer and wider then the tang. My question is what are (usually) the accepted tolerances? I understand that there's no standard, so to speak, but maybe a basic rule of thumb exists. Thank you.
Alex A Posted March 27, 2013 Report Posted March 27, 2013 In an ideal world Adrian a bang on fit will do nicely, obviously not so tight that its difficult to push on. Alex.
Adrian Posted March 27, 2013 Author Report Posted March 27, 2013 Well yes, but we don't live in an ideal world Also if the fit was so tight, they would scratch the nagako. So I guess some tolerances are accepted, but I'm wondering within which limits.
Alex A Posted March 27, 2013 Report Posted March 27, 2013 Slightly larger than the nakago, no need for a micrometer. Alex
Adrian Posted March 27, 2013 Author Report Posted March 27, 2013 Alex, what I'm trying to achieve here is to find out if this "slightly" has a definite upper limit Especially for tsuba.
Kevin Adams Posted March 27, 2013 Report Posted March 27, 2013 I don't understand, why the need for an "upper limit" of "engineering tolerance"? The language itself is suggestive of an average across a large number of produced pieces. Tosogu would be made to fit an individual blade. If existing pieces were fitted to a different blade after crafting, presumeably they would be modified to do so (sekigane on the nakago-ana, for example). Not so tight as to restrict mounting, not so loose as to permit movement after mounting. I doubt even the craftsmen could (or WOULD) assign specific numbers to this...
Alex A Posted March 27, 2013 Report Posted March 27, 2013 Adrian, am i wrong to assume the tsuba on your wak has a bit too much movement? is this your concern? Alex
Adrian Posted March 28, 2013 Author Report Posted March 28, 2013 Alex, you're wrong, the tsuba doesn't move one bit (but again I didn't tried really hard to move it) However, I was somehow expecting that all the individual pieces have a very close fit (something like the bang-on fit you described on your first post). Which isn't the case. The tsuba (and both seppas) have a rather close fit on the front-back axis of the nagako-ana (the tsuba due to seki-gane). However the left-right axis has (on all 3 pieces) a higher tolerance then what I was expecting. So I was curious if this is normal or not. Tosogu would be made to fit an individual blade. If existing pieces were fitted to a different blade after crafting, presumeably they would be modified to do so (sekigane on the nakago-ana, for example). Not so tight as to restrict mounting, not so loose as to permit movement after mounting. I doubt even the craftsmen could (or WOULD) assign specific numbers to this... Kevin, I wasn't looking for a specific number (as in "maximum .25mm on either side of the blade") . More for something like "half milimeter on either side of the blade is OK for a seppa" Just looking to figure out what the average fit would mean number-wise.
Brian Posted March 28, 2013 Report Posted March 28, 2013 Sorry, but a rather bizarre question. The fact is, you get it as close as possible with as little movement as possible. As long as it still goes on, that is a good fit. Very simple, no rebuttal required. Brian
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