Hi Terry... Sounds like you pretty much have the gist of it as I suspected. As to the radii of the cauls... yes we (I in any case) don't know the radii along each rib, and yes you don't necessarily need to dry to 4 % to get the same crown with 5 % dry down if you compensate with a caul with an appropriately small caul. All that said... one has to assume that whatever the rest of their procedure is... it is pretty much the same as it always has been... so the 4% vs 5.5% discrepancy becomes quite significant. And in anycase... its kinda nice to once an for all get at least this much straight on this list as to dry down percentages at NY S&S. Cheers RicB I don't know what the exact implications would be with let's say panel ribbing done at 5.5% vs 4%. Obviously, with everything else being equal, the 4% would develop more crown. But I've never built such a board. I do know that ribbing done in the range of 6.0% to 6.5 % doesn't develop much compression crown at 50% RH room conditions. I really don't know, but based on my very limited experience with compression crowning, I should think that ribbing done at 5.5% wouldn't produce enough crown for a compression crowned board - but then again, we don't know the radius (radii) of the cauls used when pressing - do we? You don't have to dry a panel down at all to produce a compression crowned soundboard if you press the straight ribs and panel into a small radius enough caul. Dunno. Terry Farrell ----- Original Message ----- > Yes... that was the only real difference. 5.5 % versus 3.8%-4.5% > depending on the season. As to the significance I attach to that > difference, I dont think I need tell you about any of the implications > there :) Thats quite a large difference if these are glue up stats. > > RicB
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