> I have measured the keybed to the string height and keybed to the >hammer flange center pin to get the boring distance for some grand hammers. Greetings, Is the string parallel with the keybed? I don't think that the linear difference between centerpin and string height tells the whole story. Scribe a straight line on the hammer's side, mount it on a shank at 90 degrees, and then measure (with a small square) what the angle is between string and hammer when the action is in place? It is not uncommon for the strings to rise rather steeply upward toward the bridge in the last octave or so. Either hanging angle or bore distance(or both) must be compromised to have the hammer and string perpendicular upon impact. A caution though, overshortening the bore distance in an attempt to square the hammer to string can make regulation a distant dream, and it is essential that things like let-off and drop are still within reach with the adjustments available. Regards, Ed Foote
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