This is actually a very good point. As others have stated one doesnt really want too loose a jack pin as a result. That said what Jim says holds true. Repetition and other related problems are far more likely to occur if the jack center is tighter then the balancier center. One other point. 6-9 grams of balancier center friction should be more then enough to take this moment out of the checking problem. If you have a perfect action regulation and good friction tolerances for centers and your geometry is even reasonably good, along with nice clean fat free tails and solid back check wire roots... then you should have no problems getting a good check. IME 90% of the time, shaky checking is due to some instablity action moment. Too loose hammer centers... heavy and hopping dampers... mis aligned back checks... loose (even barely loose) back check wires... anything that can shake rattle and roll at the critical moment of check. The rest of the time it has to do with the checks and/or tails themselves. I'm not ruling out the significance of the balancier pin tightness... I'm just saying I've yet to have to address a checking problem this way. Repitition problems on the other hand can easily get wrapped up in the centers of the jack and balancier. Wims problem may of course be a weird one... they most certainly come along from time to time. But I have to think that with the repinning already done... the problem lies elsewhere. Cheers RicB Balancier tightness has been a very interesting discussion, and I don't think I can add much to what has already been said, except for one thing. I don't remember who said it, or when, but it had to do with pinning the jack as tightly as the balancier. I don't agree with that. You are far more likely to have repetition problems due to a jack that's too tight than you are with one that's too lose. Sincerely, Jim Ellis
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