Conrad Hoffsommer wrote: > At 07:23 AM 8/26/2005 -0400, you wrote: > >> Could it be caused by unequal friction on each side of the bushing? >> >> --Cy Shuster-- >> Boston, MA > > Sorry, I've lost the initial post, but when I find that inconsistent > striking, it is due to unevenly worn bushings or a broken/splitting > birdseye or flange. Were the centerlines of jack and knuckle/butt > lined up? > > I suppose a loose flange screw could do it, but the noise of that > would have been very noticable. > > Conrad Hoffsommer > I tried to get a life once but they were all out of stock. > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > > Yes, the jack alignment to butt is OK, and the pinning seems OK, > too, that is, as good as any of the other butts/flanges that do NOT > wobble when striking. I don't have a way to scientifically check that > the center pin torque on each side of the flange is exactly equal -- > just the usual methods of checking "by feel," clamping in a vise and > checking for wobble, hanging upside down and checking number of swings > (there were 3 or 4). I pushed the hammer lightly to the unison to see > if it's striking all three strings simultaneously, which it appears to > be doing -- except on a hard blow, some of these shanks twist, I > think, or the ears of the flange twist, or the bushing "gives" a bit, > causing the hammer to strike at an angle or to the left or right of > the unison. Occasionally I encounter this on grands also, when tuning -- play it soft and it hits all three; play it loud and it misses a string, or vice versa. --D.N.
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