I wrote:
“When the damper pedal is set to lift the dampers almost as high as the keys, and the upstop rail is set to touch the underlevers when they are lifted by the key end felts, you will find an increased amount of travel in the underlevers when the pedal is not employed.”
Paul writes:
> I understand everything you said except the above statement.
When the tray is lifted, the underlevers' centerpins are raised, since they are on a radius (proximally) from the axis of rotation of the tray.
Assume the key has lifted the underlever, so it is held by the key end felt at one end and its centerpin at the other. Now, lower the stop rail until it touches the top of the underlever and it can't move upwards. If you now raise the tray while holding the key down, the tray will lift the centerpin upwards, creating a downward force by using the stoprail as a fulcrum. In extreme examples, the pedal can be felt in the key, or aftertouch can get a totally uneven feeling with the pedal down. It can hide as bad keydip when keys are stopped by the rail's inteference at the distal end instead of the front punching under the finger.
To prevent excessive wear on the upstop rail, as well as avoid all sorts of weird feeling down there in the aftertouch area, I have to set the upstop rail higher than ideal for key playing, just so that if we hit the pedal while we have a key depressed,(it happens), we won't be trying to force the keyend down. This increased clearance is a high price to pay for a simple engineering error. It is easy to remedy if you are ready to redrill the tray blocks and move pins around.
Jon Page has posted some of his conversions, in which the centers are shared by underlever and tray. It makes a world of difference in taking that slap out of the feel of the piano.
Hope that helps
Ed Foote RPT
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