As Bill pointed out, it's the front to back placement of the plate, not the height, that determines the capstan position. The farther in that they set the plate, the farther the capstan goes with it. Actions are fit to the belly with the keyframe in a fixed position by determining the strike point and with the hammers glued on at a fixed 130 mm. The capstan is set also at a specific position with respect to the center of the wippen cushion. This causes a variation in key ratio. You know the rest. On the other issue, (and response to Terry as well) the Kawai did not have the same problems with changes in friction. I frequently find that new Steinway parts do not do well with humidity swings (Renner has the same problem). I encounter sticking jacks, hammer and damper flange problems on new NY Steinways all the time. Interestingly, these problems do not seem to appear in the showroom (air conditioned to compensate for lots of hot lights, i.e. low humidity), but occur frequently once the piano is moved out to the customers home where humidity (at least in this area) is always much higher. David Love davidlovepianos@earthlink.net > [Original Message] > From: Richard Brekne <Richard.Brekne@grieg.uib.no> > To: Pianotech <pianotech@ptg.org> > Date: 8/28/2003 8:38:29 AM > Subject: Re: Dampp Chaser and Grand Action > > > > Farrell wrote: > > > Unfortunately, I believe that this is another plate indexing problem in which the capstan is located too far back and the ratio is just too high producing a very heavy feeling action." > > This thingy about plate height being the determinant for capstan placement has been vaguely put up a few times in the past couple years and I have yet to get a finger on exactly how that works out. Just what, step by step proceedure do factories use to get from <<plate height>> (over keybed ?) to capstan placement ? > > Detailed explanation would be reallllly appreciated. Goes to some of Stanwoods proceedures, some of Baldersins (and others) criticisms of those, and represents one of those "far to many" holes in my own knowledge. > > Thanks > > RicB > > > -- > Richard Brekne > RPT, N.P.T.F. > UiB, Bergen, Norway > mailto:rbrekne@broadpark.no > http://home.broadpark.no/~rbrekne/ricmain.html > http://www.hf.uib.no/grieg/personer/cv_RB.html > > > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives
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