Hi, As you compress a 100 per unit spring one unit it pushes back with 100. After two units it is pushing back at 200--but it is *not* more rigid. At 06:37 AM 2/4/2004 -0800, you wrote: >Hunh? When was thelast time you compressed a spring by >hand??? Everyone I've ever compressed definitely >offers more resistance ( stiffness) the further it is >bent, or compacted. > Twoing > >--- Phillip Ford <fordpiano@earthlink.net> wrote: >> > >At the risk of oversimplification, isn't a >> crowned soundboard just a big >> > >spring, the more you compress it, the more rigid >> it becomes? >> > > >> > >David Love >> > >davidlovepianos@earthlink.net >> > > >> > >> >David, >> > >> >This is the point that I was trying to make. I >> believe that the >> >soundboard is essentially just a big spring. A >> spring doesn't get >> >more rigid or stiff the more you compress it. >> Within its working >> >range it has a constant spring rate or stiffness. >> ... If the board is >> >actually getting stiffer as a result of applied >> load then it's not >> >acting like a spring or a beam, and I would like to >> understand what >> >mechanism is causing that to happen. >> > >> >Phil Ford >> > >> > Phil >> > If this is true then why can I measure a >> predictable amount of residual >> > bearing at the bridge after the board is string? >> >> You could do that whether the spring rate was linear >> or non-linear. Let's >> say you put on 1 1/2 degrees of bearing everywhere. >> Let's say that the >> bridge sinking 1/10 inch would decrease that to 1/2 >> degree bearing. Let's >> say for the sake of argument that the spring rate of >> the board is uniformly >> a linear 1000 lbs/in. everywhere. Let's say total >> downward load from the >> bearing is 100 lbs. This would result in a >> predictable and measurable 1/2 >> degree bearing after stringing. >> >> I don't see that the board spring rate has to be >> non-linear (the board >> doesn't have to be stiffening as you load it) in >> order to end up with >> bearing after stringing. >> >> >> > I thinkthe boards compression rate is non >> linear. At least that's the >> > wya it behaves in my hands. >> > DAle >> >> >> You may be right. But I'm going to have to see some >> measurements to be >> convinced. >> >> Phil >> >> >> >> >> _______________________________________________ >> pianotech list info: >https://www.moypiano.com/resources/#archives > > >__________________________________ >Do you Yahoo!? >Yahoo! SiteBuilder - Free web site building tool. Try it! >http://webhosting.yahoo.com/ps/sb/ >_______________________________________________ >pianotech list info: https://www.moypiano.com/resources/#archives > > Regards, Don Rose, B.Mus., A.M.U.S., A.MUS., R.P.T. mailto:pianotuna@accesscomm.ca http://us.geocities.com/drpt1948/ 3004 Grant Rd. REGINA, SK S4S 5G7 306-352-3620 or 1-888-29t-uner
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