Ron, Your "response" as it were, avoided answering the basic question that I posed: that a board constrained by the rim glue joint will have the forces you observed re-directed outwardly. And you indulged in insult and rudeness to a post which I very diligently tried to make as polite and objective as possible, for the mutual benefit of all readers. These two aspects of your "response" can only detract from your credibility. I have no doubt that if I replicated the experiment you created, I would observe the same effect. But your setup does not mirror a board installed in a rim, where other factors come in to play. Right??? Please abandon the invective and address the actual question at hand. Thank You, Thump --- Ron Nossaman <RNossaman@cox.net> wrote: > > >Dear Mr.Nossaman, > > I thank you for attempting to empirically > >demonstrate the effect of downbearing, on a > "mock-up" > >of a soundboard panel and rib. And I thank you for > >your very polite description, which has added to my > >understanding of the forces involved. > > Still, I remain skeptical of your > explanation. > > You claim to have seen the board ends come > INWARD > >as pressure is applied to the crown's apex---- and > I > >would never call an eyewitness a liar! > > Yet you in effect are, and have - twice. > > > > But I am sure > >that you realize this contradicts common perception > >and observation, to say nothing of the laws of > >physics. > > I realize no such thing. Gordon, have you actually > tried it, or are you > speaking for common perception, observation, and the > laws of physics from a > position of pure speculation? > > > >Unless something else is at work here! > > What is at work here is what Phil Ford and I > discussed, that soundboard > crown is not an arch in the first place in spite of > someone's intuitive > impression that it must be so. Refer to our > discussion for the details. > > > > The only (legal) way to end this debate may > be to > >put a very large micrometer across a piano rim and > >load the board, watching for expansion. ( Or > >contraction, as your prior assertions would seem to > >indicate.) > > Your response will be most sincerely > appreciated. > > > > Thank You! > > Thump > > Build the rib and panel model, do the test, and pay > attention. > > Ron N > > _______________________________________________ > pianotech list info: > https://www.moypiano.com/resources/#archives > __________________________________ Do you Yahoo!? Yahoo! Finance: Get your refund fast by filing online. http://taxes.yahoo.com/filing.html
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