Repost: Help! My capstans are too short!

Ron Nossaman RNossaman@KSCABLE.com
Wed, 29 May 2002 22:58:29 -0500


>Tom,
>     I hope the end of the key does not rise above the "what you ma call it" 
>when you shim the rails. 
>
>Tommy Black 

Hi Tommy,
My thoughts were that the action function was reported to be fine before
case repairs were done. After repairs, this thing showed up. What happened?
If the action is at a different height than it was originally, neither the
string grooves in the hammers, nor the dampers would mate with the strings.
That wasn't reported to be the case, so the action height probably didn't
change (much) with the repair. If the action height didn't change, then
either the keybed height didn't change either, or the action supports (ball
bolts, or whatever???) were screwed up to reposition the action after the
repair left the keybed too low. If the action is in the right place
relative to the strings, then it just about has to be the key frame that's
not at the right height. If the ball bolts were adjusted, that would
account for it, or if the key frame was removed to make the repairs, and
whatever shims that were under the key frame were possibly not included in
the reassembly - that would account for it too. Since the key frame, cheek
blocks, name board, and key slip all index off of the keybed, some trial
fitting needs to me done to see if there is enough clearance between the
key and the name board to shim both the back rail and center rail of the
key frame up enough to let the capstans reach the wippens. If the key hits
the whoositz, it ain't gonna work, and it gets a whole lot more expensive
to fix. The trick in this case is guessing right as to what the heck
actually happened that accounts for the condition the piano is currently
in, and correcting the problem that's causing the problem instead of
introducing more problems by modifying what wasn't really the problem in
the first place, in the attempt. So if the keybed is in about the right
place (a good chance, in my estimation, since there aren't too many ways to
get it at the wrong height during a repair), then the key frame is the
likely culprit. The back and center rails can be shimmed up leaving the
front key height where it was, or wherever it's needed. It's further back
where the key needs to clear the name board felt that needs the attention. 

Or I may be entirely mistaken and it's something else altogether. 
 
Ron N


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