Ed Foote says a jack will move just as fast when pinned with 6 grams friction as with zero friction. (Ed, six grams measured where?) All other things being equal, no, that's not quite true, but it is true that it may still move faster than it needs to move, i.e., as fast as it can clear the knuckle. But this is NOT what I'm talking about. I AM talking about the thing being so tight that it simply fails to repeat, regardless of repetition speed. In fact, this type of failure is more apt to occur with slow soft playing than it is with rapid forceful playing. You may have fairly tight jack pinning and great repetition at one time under fast repetition, but it may later tighten up for whatever reason, and just simply fail at the worst possible time. The pianist will be playing a soft, slow, expressive passage, and "PLOP". The key will go down, and the backcheck will grab the hammer tail. I have had it happen, and so have others - even with jack pinning that came straight from the factory. I'll opt for a jack with some safety margin that's free to move without being wobbly loose. Jim Ellis
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