Paul and List, This is a good one! Three of us sat around this morning trying to figure it out, and managed to come up with more questions than answers - e.g.. How old is the piano? Are the repetitions original? Are the hammers glued at the same place on the shank? What is the keyheight? General consensus was that both problems are probably related to stack height and/or the new parts. Larger Renner hammers, a stack which is too low, and (if the reps are new) a change in the repetition profile could all be the culprits. It does seem that the blow is narrow and dip is shallow. These should both be increased by lowering the capstans. This will have the added benefit of solving the jack problem (test this out on any action). Making this adjustment with the backchecks out of the way should simplify and clarify the situation. Unfortunately, it will aggravate the hammer/backcheck problem. How high are the backchecks? What is the distance between hammer tail and backcheck at let-off (should be 1-2 mm)? How much larger are the new hammers? This one is very hard to diagnose without seeing the piano, but raising stack height might give you the clearance you need. Or, it might be necessary to trim some felt off of the hammer. This solution has been used in some settings where very high checking was required for maximum repetition. Whatever course of action you choose, keep in mind that the way the action plays is more important than measurements, it is not unusual for the jack to make some contact with the felt on the balancier, and the simple solution is always the best solution. This post was prepared with significant input from Gary Green, Steve Marcy, and Kevin Stock. Stephen Dove STEINWAY & SONS New York -----Original Message----- From: NBWW@aol.com [SMTP:NBWW@aol.com] Sent: Wednesday, July 22, 1998 9:45 AM To: pianotech@ptg.org Subject: stuck List I was asked to regulate a Steinway B. What I found has me stuck. Two things. When the hammers drop after releasing the keys they hit the top of the back checks. Hammers are bored to factory specs. Checking is very good. No amount of repositioning the back checks seemed to solve the problem without compromising their function. The sesult is a slight "bump" feeling in the key- like you get when the under lever stop rail is set too high and the dampers bounce. The other problem is the jack. With the dip at .375, blow at 1 5/8", the back of the jack is being pressed into the cushion in the back of the balancier window. It is literally captured between that cushion and the let off button. Increasing either the dip or blow distance makes the problem worse. At these settings the action functions and feels good to me. I've done a lot of regulating in 22 years and I'm still learning, but I can't make sense out of these problems. I've seen the hammer problem on a Steinway D once and the jack problem on a Kawai GS 60. What have I missed? The college is trying the piano today and I'm calling them next week for a report. There is evidence of other techs attempts to deal with this piano and the current tech is smart enough to know its over his head. He's grateful to find some one to pursue the problems- for there are many Steinways on the campus and in town that have no one to service beyond tuning and some regulating. Am I standing too close to the trees to see the forest? Paul Chick RPT
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