MIKE writes: As the capstan/wippen moves thru its > rotation the capstan moves upwards & rotates to the middle of the > capstan & then to the rear edge. SO, as it continues thru its arc, the > point at which the wippen is lifted moves to the rear edge of the > capstan & closer to the wippen pin thereby accelerating the key/action > motion. Kind of an automatic transmission affect.Things move faster > without shifting.< > Other things being equal, the action ratio is determined by where on the whippen the capstan is at any moment. It is difficult to have the same ratio at the beginning of the key stroke as is obtained at the end. If the at-rest position has the contact at the magic line, the ratio will decrease throughout the stroke. If the contact reaches the magic line at the halfway point, the ratio will increase up to that point and then decrease during the last half. This is because as soon as the contact point passes the "magic line", the action ratio begins to decrease, since the contact point begins moving away from the whippen center. I find the best response is to be had when the contact point reaches the magic line at let-off. What is happening in this configuration is that as the key begins to move, the beginning ratio is at its lowest; a "first gear" if you will, and the point of maximum ratio occurs when the hammer is at its maximum acceleration, (highest gear). I think we want the minimum friction to occur at the moment of fastest motion of the key, and the rising rate produces this. If the ratio "falls off" during the last half of the stroke, it is working against acceleration of the action by the key, which means a fall-off of acceleration relative to the speed of the key. regards, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html ************** A Good Credit Score is 700 or Above. See yours in just 2 easy steps! (http://pr.atwola.com/promoclk/100126575x1220439616x1201372437/aol?redir=http:%2F%2Fwww.freecreditreport.com%2Fpm%2Fdefault.aspx%3Fsc%3D668072%26hmpgID %3D62%26bcd%3DfebemailfooterNO62) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090315/129ce5a7/attachment.html>
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