Jon observes: >>While you're at it, check the angle of the underlevers. If they are too steep, lower the pivot hole.I'll be doing that on an M today. The underlevers are pitched downwards so much that there isexcessive sliding friction on the key end felts. Fortunately the piano has not had a lot of useso there are no trenches plowed outs.I like to have the key lift the underlever to being parallel with the keybed at full keystroke.This reduces the sliding friction to the minimum, near zero at full depression.-- Regards,Jon Page Greetings, It seems that the factory just overlooked the geometry in the 1960's. How the engineers of the short Teflon back actions ever thought they would work well is beyond me. I also like to make the arcs described by key and underlever share some of that magic line thinking. I suppose minimal slide would require that the contact point be on the magic line at half stroke, but I question whether it makes much difference if it hits the line at the end. It seems that having the underlever horizontal when at rest would apply the maximum weight on the string, and cause the sliding action to less than that which occurs when the underlever is sloping down. I don't know that there is room to lower the tray that much in most cases, so I also often leave them as Jon mentioned. Does anybody smooth the wooden contact point on the underlevers with, say, 400 grit paper and a spray of Teflon ?? Maybe, even burnished graphite?? Just asking,wondering if there is anybody else out there that has run out of things to try........ Regards, Ed Foote RPT http://www.piano-tuners.org/edfoote/well_tempered_piano.html
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