> > > As far as the panel cross grain not holding the required compression >> loads, how much is it supposed to hold? I agree that it won't hold >> the entire downbearing load. On good spruce isn't cross grain >> compression strength on the order of 500 psi? Let's say you want to >> stay below 200 psi to prevent compression set. > >That still won't "prevent" compression set. It will simply slow it down. >Any significant load on the wood will induce compression set--especially >perpendicular-to-grain. > >Del This is discouraging. Are you saying that there is no lower limit below which there won't be compression set? If so then every soundboard is doomed to flatten. Even on rib crowned boards the ribs are subject to some level of compression load on their upper fibers due to the bending loads imposed by the downbearing. Phil Ford
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