Phil, I would advise checking the bedding of the key frame. I did an action conversion on a Moore & Moore, (circa 1870's), that, originally did not have bedding bolts on the key frame. I had the same problem. Darn bass hammers would not check. The lower you played the worse it got. I installed bedding bolts, adjusted same, and the problem went away. I speculate that the key frame did not match the key bed. One of the problems with this piano, originally, was that it had "cheek lift". Big clue there, that I kinda missed. <G> I hope this helps. Regards, Joe Garrett, RPT, (Oregon)
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