Hi Terry... I'll just take this bit here as it seems like we are on the same page at this point.... comment below it all > If the edges are strong enough to keep the panel from crowning, then it > would seem to me that they are strong enough to help support crown if they > were first asked to..... which of course is a different question all > together. Well, actually, that is what I thought you were asking. I agree, that if one believes that rim constraint causes crown, then a panel edge that resisted crushing would indeed be part of a crown-making system. My point is... that Ron's experiment shows clearly the end grain of the top half of the panel will not crush as advertised in some of the argumentation against the buttressed arch idea. Indeed... it is strong enough to <<buttress>> his experimental panel bit against crowning. So the "end grain will simply crush" argument appears clearly disproved by his experiment. Whether or not the soundboard actually behaves in such a manner that this same edge wood would actually exert outward pressure on the rim in the face of increase down bearing ... or as Ron suggests do the exact opposite... is another question entirely. But if it actually DID exert outward pressure... it seems clearly demonstrated by his own experiment that the end grain would not simply crush. It would hold stand as it did in his experiment. Cheers RicB
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