Ron Nossaman wrote: > > I'd say your explanation is right. The described arcs are intersecting, > rather than tangent, and the radii of both arcs (wippen flange center to > jack top, and hammer flange center to knuckle contact point) are decreasing > as the jack rises. I don't understand why widening the spread would change > this. Seems like that just tilts the jack forward more and makes the wippen > arc radius longer. Wouldn't that make it worse???? Take an action model and set it up like this and see for yourself, remembering there is a difference between the jack being "dragged backwards by the knuckle" and "rocking" on the knuckle. In anycase... in the later the jack doesnt compress against the felt. -- Richard Brekne RPT, N.P.T.F. Bergen, Norway
This PTG archive page provided courtesy of Moy Piano Service, LLC