Hi Ron. Thanks for the informational post. Definantly a keeper. This paragraph caught my eye and prompted the following querry. As with all lever systems there are three leverage concerns yes ?? Lift ratio, speed ratio, and weight ratio. Now I havent really thought about the pedals with these in mind before so I'm out fishing as it were. But it would seem to me that perhaps all three would be worth taking into consideration. Speed ratio gets into the control a pianist feels in the action... and I would assume the same (in principle) holds true here. Weight ratio would come into play if the the weight being lifted was more then appropriate for the leverage. And then there are these points you sketch relative to the distance ratio. What I'm wondering is how much thought has gone into the pedal / trapwork design with all these in mind. Any thoughts you (or anyone else) might have would be welcome. Cheers RicB The lift ratio and the resistance of the pedal system are two separate issues, regarding the performance of the sustain pedal. Most manufacturers fit a return spring to the damper lift tray, the sustain lever directly under the keybed, or both. The return spring on the damper lift tray can create problems over the longer term, since its not usually possible to position the spring directly over the push rod. When the return spring is offset from the push rod, the damper lift tray can develop a compression-set warp over a number of decades. This is a long term problem which won't usually occur while those who built the piano are alive. Eventually, once the builders are lying quietly in a box on a hillside somewhere, some repair tech in a workshop might be found whining about another case of poor design staring them in the face, as they deal with a warped damper lift tray. snip... Ron Overs
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