" . . . I think that I have absorbed the principles of coinciding arcs,
key ratio, and so on, that underlie the grand piano. . ."
The geometry of good uprights are no less critical than in a grand.
Coinciding arcs apply equally.
Look in your supply house catalogs for a book explaining upright
geometry. No higher math required than being able to count to ten on
you fingers. (About all I can do.) It is a good book and will explain
tolerances and how to compensate for stickers and dowel capstans.
My library is in storage.
Newton
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