Hi folks Spent about 40 minutes today with my handy dandly grand action model looking at what happens when the jack top is too high relative to the window. I can say pretty conclusively a high jack top in itself is not going to cause drop to dissapear. Nor should it really. If you take a perfectly regulated action and then lower the repition lever so that the jack top gets becomes high in the window you've done essentially two things. One; you have caused the jack to have difficulty returning under the knuckle, and two; you've cause drop timing to be delayed a bit. This is where the symptom may seem to occur. If you have a very tight regulation with regard to letoff to begin with, AND dont do insure that lett off and drop engage at the same time, AND have the jack just a tad high, then when when the jack trips the rep lever stays in motion and the hammer <<falls>> whatever little distance the jacktop is high in the window.... until the rep lever gets engaged. There is one spot where this appears like no drop.. looks to be when the jack is about 0.5 mm over the repetition arm window. But its largely an illusion as drop is just smoothed out and melded into what is normal aftertouch motion. If you have letoff set a bit more conservatively to begin with... or if you insure that the letoff button and jack button engage at the same time... then drop occurs as usual regardless of jack top / rep lever height. Cheers RicB
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