>What you're actually doing is changing the action ratio by >moving the fulcrum Installing a half punching under the key has more effect of maintaining the position of the fulcrum. As the key is depressed on a normal punching, the fulcrum migrates forwards as the key rocks on the punching. Trimming the punching removes the front portion thus not allowing the fulcrum to travel too much forwards of the pin. This is the benefit of S&S Balance Rail Bearings, (as difficult as they are to level keys). -- Regards, Jon Page -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20100107/b18734f5/attachment.htm>
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