Add to my last post... Also, how far off from half stroke is the existing line of centers? The capstan heel "pivot" is not a pivot either, but a sliding pivot. There a 3 non-pivots that are considered to be mathematically true pivots in any leverage calc. Any one, or the cumulative effect of all three can cause the "as functioning" leverage to disagree with the simple math. Then add to that that the actual location of the "as functioning" key levers can be pivoting forward of the center of the balance hole, and you you have 4 sources of measurement noise. Further, since the key in particular is a long arm lever the effect of small measurement vs "as functioning" pivot locations is greatly accentuated. I say, keep it simple. The existing leverage calculators we use are approximations. Keep the calcs simple as they work reasonably reliably as a general average, and look for measurement vs "as functioning" anomalies to explain gross difference. Jim Ialeggio -- Jim Ialeggio jim at grandpianosolutions.com 978 425-9026 Shirley Center, MA
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