CAF can be caused by a variety of things and some combinations of things, a list too long to go into here (for me now). But the two single most common causes and their combination, are loose balancier pinning and hammers regulated too high off the rest cushions. The two together are a guaranteed train wreck of lock-up on fast repetition. Jeff T. is right when he says sluggish pinning of rep lever and jacks or weak springs are problems, well yes, that is obvious, but it's when the balancier is too loose that the real trouble begins. No matter how tightly you adjust that spring it can be pushed down by a heavy hammer returning on a heavy blow. Disaster. Pin balancier centers 4-9 grams (depending on how high your humidity gets in the summer) for best results. As for raising the stack to improve the distance between rest cushion and shank this definitely helps as long as you are not creating other problems like destroying the magic line underneath at the capstan. Doesn't everyone have Mike Mohr's Steinway forefinishing notes? Anyway 3 3/4" is the wippen center height spec. When you make this adjustment you need to spin the whole stack on the hammer center pin axis so as not to throw off your strike point. Equal shim amounts on front and back cleats is usually wrong. This is way too complex for email. sorry just had to chime in. Chris Solliday -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/caut.php/attachments/20090814/9763a18d/attachment.htm>
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