>Ron, > How is this done? and what ranges are you looking for? I use a heavily modified and extended scaling spreadsheet. It's not that hard to assign expected bearing angles to each unison and figure the resulting downbearing from the string tension and angle. The unison loads are assigned to ribs according to the proposed rib layout, and a simple beam deflection formula gives me some idea of how much load the rib will take. I graph initial crown and deflection under load, so I can watch the results of any changes I make. Not much point in designing a rib set that won't support the bearing I want to put on it and still have positive crown. I juggle number and placement of ribs, as well as lengths, widths, depths, and crown heights against expected load, and attempt to make reasonable decisions as to the best balances for the different areas of the scale. No absolutes, but I find it worlds more informative than simply copying what was there with no idea of what that really is. While I can, have, and do make decisions based on nothing whatsoever, I prefer making them from as detailed and understandable an information base as I can get - or generate. Ron N
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