This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment David, How did you mesure the ratio ? By weighting or measure ? Thanks. Isaac -----Message d'origine----- De : owner-pianotech@ptg.org [mailto:owner-pianotech@ptg.org]De la part de David Love Envoyé : vendredi 15 février 2002 16:31 À : Pianotech Objet : Unequal key ratios: puzzler Recently rebuilt a S&S model S c 1931. The measured key ratios for the sharps were .48, for the naturals .51. I considered moving the capstans on the sharps so the total leverage on each would be equal. But when I started to set up samples and take measurements, I found that the FW pattern was smooth and the corresponding SWR's were equal. I would have expected that sharps to need less FW or, with a smooth line front weighting, a varied SWR. Somewhere in the system something else compensated for the different key ratios. Question is where? All new parts, strike weights smoothed, BW all equal. the job is now completed. I left the capstan positions alone and the FW curve was pretty smooth, SWR all 5.9 - 6.0. A few bumps along the road as is often the case, but one would have expected 6-10 grams less FW on the sharps. Any opinions? David Love ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/a5/5a/12/22/attachment.htm ---------------------- multipart/alternative attachment--
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