What I was referring to is what Ric described, where the hammer gets jammed and held down by the backcheck. What you're describing, I would call a checking issue, where the hammer tail drives through the check too far on a hard blow and the jack can't reset. I suppose I learned regulation on pianos where the shanks were high off the cushions, so I learned to make them work that way. I can't recall ever having seen shank packing marks on wip cushions. I also tend to dislike systems where you are forced to have cushions so close, and I really don't like rails. If the hammer is bouncing off the cushion, something ain't catching it right. If the cushion is coming into play, then the stage is actually set for CAF. So, yes, the cushion is a fail safe for when the action is not well regulated. Jeff ----- Original Message ----- From: Fred Sturm There are a couple things here. First, there is the question of what we are calling "CAF." I am referring to a particular lock up of the action (of one note of the action), where the hammer ends up well below the hammerline, and it doesn't reset immediately. It sometimes resets within a second, but that is too slow. Sometimes it resets if you just lightly touch the key. Sometimes it stays locked until the key is depressed a couple times. It is, as I said before, a fairly rare symptom, which occurs with particular sorts of playing, but can be very, very aggravating to someone who plays that way, or plays particular passages. I, just like you, have had pianos with hammers high off cushions with zero complaints. And then, if somebody else plays the piano, the problem occurs. And, I repeat, and with emphasis, the only cure is a closer cushion. Talking about this precise problem, not about "action failure" in general. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut.php/attachments/20090817/39a867d6/attachment-0001.htm>
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