JIm: Did you develop any data with this, take any pictures, create documentation etc. that would be helpful, write-able up? Please? Thanks, and happy new year... Paul In a message dated 12/31/2009 11:23:04 A.M. Central Standard Time, jimialeggio at gmail.com writes: David Love wrote: > > On these pianos, then, the panel is going through quite a distortion > of being pushed down in one area and pulled up in another, a sort of > soundboard scoliosis. It’s no wonder that these types of instruments > often have some distortion and a dramatically changing tonal character > as you go through the scale. > I recently set up an extended series of rib/bridge deflection test using a 1/3 scale model rib/bridge system with scaled downbearing loads applied at each rib. The point was to get an idea of where the downbearing loads actually get distributed to. Deflection of the bridge at each rib was measured in various loading scenarios. Observing the distortion that David describes was quite real and very illuminating...watching it happen as I applied weights rib by rib, really etched the image in my brain. With an inappropriate or failed rib/board system the whole thing can squirm like a snake. With appropriately sized belly components, the deflection becomes a smooth predictable trend...very interesting, and especially helpful in coming up with data to properly assign rib loads throughout the scale. Jim I Grandpianosolutions.com(almost launched) -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech.php/attachments/20091231/cbc865f9/attachment.htm>
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