> > After Ron Nossman's quick nudge, I figured out my difficulty. You're speaking > of the deflection as only being one right triangle, I'd been seeing two, > which of course there are. Exactly. Baseline speaking length, break right x°, across bridge, break left x°, continue parallel to speaking length for an x° stagger. It usually doesn't really work exactly that way in real pianos, but that's the idea. The side bearing pressures we were discussing were per pin, rather than per string. > > Speaking about the empirical measurements which engineers prefer, a few years > back I dreamed of a way of measuring the total friction barrier presented by > the bridge to the string, that is, its pair of staggered, slanted pins and > the wooden surface between them. -------------------- > > Bill Ballard RPT > NH Chapter, P.T.G. A workable enough approach, near as I can tell, though it's about rendering a string through the bridge rather than what it takes to push one up a bridge pin. Even so, it's another worthy direction of inquiry. Now tell me if the "tuned" rear duplex contingent would accept the resulting data as prima facie evidence that they are barking up the wrong segment in their quest for piano tone Nirvana when they find out how seldom the speaking length tension matches the scale tension. > > "We mustn't underestimate our power of teamwork." > ...........Bob Davis RPT, pianotech '97 "Nor neglect the imperative of individual thought." ...............Uncle Wookie, RPT - PDQ - BFD - Pat pend, pianotech 'now Ron N
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