Play at keyframe guide

[A440A@aol.com]

Tom M.  writes;

>.. it is not uncommon in the machine world for the harder material (steel)
to be worn down by the softer (brass, bronze, even rubber).

     This is why the aluminum piston in a motor, is still the same size even
when the iron cylinder walls are worn into a curve.

     At last request,  the Steinway factory sent me cast, treble-style
key-block plates for both ends.    Is this all that is available?   Must I
really machine, either the block, or the brass casting?
     And Who has the definitive, accurate way, to hold tight tolerances,when
 plugging the keyframe holes and retapping  for the smaller diameter threads
on the newer style square pins?
     (Geez, I wish the engineers had had to replace a schools worth of of old
style guide pins with new,  They would have learned the word "fungible" !)

Regards,
Ed Foote
Precision Piano Works
Nashville.