,At 10:55 AM 3/12/98 -0500, you wrote: > >Butt springs should be even. Butt springs have very little leverage, >but they are very important for repitition. > For a chapter technical last year, I tried a touchweight experiment on a vertical action model(Sohmer?). The variables were 1)hammer weight, 2)Flange friction, and 3)Return spring strength. Substituting a 12 gr. bass hammer for a 6 gr. treble hammer increased downweight by 6 grams. Substituting a 'one swing' hammer flange for a 'perpetual motion machine' flange increased downweight by 6 grams. Increasing hammer return spring strength from negligible to maximum, by bending only, increased downweight by 17!!! yes that's right 17!!! grams. It might be pretty hard to accidentally bend a spring for maximum strength, though they actually look close when first installed on a rail. I'm sure this experiment would yield different results on different actions, but I think the concept would remain. Return springs have a lot of influence on touchweight. I hope this info helps. I would hate to see someone reweight keys after a action reconditioning when 5 minutes with a Hart spring tool wuld fix the problem.:-) Ken Jankura, RPT
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