Hello list, Although I still have much work to do in order to complete this action I thought that I would pass along a very interesting thing to anyone that followed the topic and helped me. John had mentioned action elevations so I dug into this: I had carefully measured much of the action geometry and concluded that the whippen rail, hammer rail and balance rails were parallel, the front and back rails were parallel but shifted in relation to the others to accommodate the key length change. I had measured the key capstan line to be parallel to neither and skewed to the whippen rail by about 3mm being closer to the whippen rail in the bass. Then John put me on to action elevations and the general target for the whip centers to be 2.5 inches below the hammer centers. The elevation of the whippen center pins above the key bed was not equal. It varied by about 3mm being lower in the bass than the treble. After correcting this (setting the height of the whippen centers at exactly 2.5" below hammer centers) I found that the action spread had increased, especially in the treble. After removing shims in the whippen rail and correcting the action spread - lo and behold - the whippen rail is now parallel to the key capstans and moving the stack is not necessary. The whippen WW value is now constant across the keyboard and other undesirable consequences are avoided. Now that was a revelation that I had no idea could be a problem. I had fully intended to move the stack in order to align it to the capstan line. I would have solved a problem by creating another. The sound advice of getting geometry correct first is a hard lesson and could have been much worse. Thanks so much to everyone for your help. Regards, Gene Nelson -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090319/534c7a50/attachment.html>
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