---------------------- multipart/alternative attachment At 05:56 PM 4/29/2005, you wrote: >At 08:57 AM 4/29/2005, you wrote: >>Thanks Roger and everyone else who responded. Would it not be easier to >>remove the springs and then accurately weight the keys.I will go back >>into my shop and play around with the springs and key weights. >> > >Hi Jack, > I have a few comments that may or may not be helpful. > >#1 Friction: It is extremely important to address ALL the friction >issues before attempting ANY weight off. Hammer shank flanges should be in >the 3-4 gram range. When holding the hammer shank and flange horizontal, >the flange should not fall under it's own weight, and should rise if the >shank is lightly tapped. (Easy to demonstrate but not so clear in >words) You need some good friction in this area for consistent >regulation, and controlled ppp playing. >Key bushings should be free, but exhibit no slop at the balance rail, and >slight side to side movement at the front rail. Balance rail holes. >Lifting the keys 1/8" at the front, they should slide down slowly under >their own weight. Using Teflon powder on the knuckles will also give you >a clearer picture of down weight. > >#2 Inertia: Increasing the leading with out doing a complete analysis of >the action geometry can be risky. The action set up may be designed to >need some spring support to give adaquate up weight. Too much lead can >lead to a sloggish action, so be carful. I would need a complete down >weight/ up weight spread sheet to give some better advice. Side by side with Identical pianos, one with assist springs supporting 10gm average, the other traditional weight off. Feed back from Profs and performance majors, was over whelming in favor of the assist springs. Both pianos was weight 54gms to 48gms, bass to treble. I used 7 sample performers. One unanimous comment, more sensitive ppp control. Voicing of both pianos, very close. This was done to minimize the psychomatic factor. Perception in every thing when correlating tone and touch. To sum up. Get all friction points within limits, fine regulation, even voicing, and a good tuning. before starting to evaluate. Regards Roger ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/c2/6e/76/00/attachment.htm ---------------------- multipart/alternative attachment--
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