That would be an interesting question, just how to measure the slightly differing speed of small parts moving fast. Perhaps this might be a time for some high-speed photography? If several notes'-worth of action parts could be removed to make room for a high-speed camera which could record both the hammer and the jack and rep lever at the same time, from the side? What method were you thinking of, Jim? Susan At 11:53 AM 12/22/2003 -0800, you wrote: >Jim, > >I would find this most interesting, myself. > >How do you propose to set up to do it? > >Best. > >Horace > > >At 11:12 AM 12/22/2003, you wrote: >>Ed, Don, Isaac, Richard, Vince, >> >>Since posting my latest memo, I have been thinking. There might be one >>case where putting more leads closer to the center of the key to reduce the >>"key" inertia might help a little bit. That is in the case of partial-blow >>repetition, where the jack just gets back under the knuckle on fast key >>release from check, and the blow is repeated before the hammer has time to >>come back to rest. In this case, the hammer has not yet come into the >>picture as far as return acceleration is concerned. It's still up in the >>air. >> >>Ed Sutton suggested some measurements, and I think that might be a good >>idea. If the concensus of the group is for it, I can do it. I would >>propose to measure the return time of the jack under the knuckel following >>sudden key release, and also the acceleration of the hammer on return from >>check. I would expect these two measurements to be quite different, and I >>would expect the reduced key inertia to allow the jack to return under the >>knuckle a little bit faster, but nothing dramatic. I would not expect much >>difference in the return time of the hammer to the rest position. >> >>All of the above would need to be done from the checked position after >>sudden key release. Anything else would simply be measuring hammer rebound >>time. >> >>It will require some set-up time to do the test, but I will do it if there >>is much interest. If not, I won't. What's your pleasure? Would you like >>me to set up the test and do the measurements? >> >>Jim Ellis
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