I've been reading all the mail about Serge's vector problem. I have a few comments. The issue is that the customer is complaining of heavy action. Is this because the capstan contact point is 1/8" off the "magic line"? Probably not. In all likelihood the geometry of this action is ok. Before you do anything, check the key bushing friction. Is there a little side play when you move the front of the key side to side? Does the key fall on the balance rail pin by its own weight? Better yet, with the stack off and extra weight temporarily placed on the back of the key, is half the difference between the downweight and upweight of the key greater than 2 grams? If so then you have significant key friction. If there appears to be significant key friction then take care of that problem first by easing all the keys and most importantly treat the key bushing felt with dry Teflon type lubricant. Then have the client tell you if the action is still too heavy. If so then my guess is that action is a little underleveraged. To check this I would suggest taking some sample strike weight and ratio measurements and see if the levels found are compatible with each other. It would be interesting if you did a little analysis on this action and reported the results to us. I suggest as a minimal survey to take upweight/downweight, strike weight/ratio data on notes 16,17,40,41,64,65. Let me know if you don't have my previous posting on the subject of strike weight/ratio. If not, I'd be happy to forward you a copy. David C. Stanwood
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