----- Original Message ----- > What I was thinking was, that if boards are glued together, then the > compression takes place. If some of those wood fibers compress, and form > the ridge, then the measurement, is less than if that portion had not > compressed more than the rest, so the crown would be less. Or is the crown > the same, because of the ribs, and the board just came in from the edges? I think I understand your question. No, the board doesn't move in from anywhere. It is glued (presumably) to the ribs and stays put. Yes, you are correct thinking that the ridge, a product of crushed wood, is no longer under compression (or less so anyway) and that small segment of panel will support less crown. So yes, presumably the crown would be reduced. But realize also that compression can damage wood cells outside of the ridge zone. Ridges formed on a panel suggest that the entire soundboard panel has been subject to some fair bit of compression, and presumably some amount of unseen wood cell damage (compression set). Likely crown has been reduced by some of that panel damage also. Terry Farrell BTW, after reading Ron N's response, I now realize what you were asking about "figuring out" the crown - you meant how do they calculate what to do during manufacturing to produce a desired amount of crown. I think Ron answered that question and your others quite eloquently. > I hope someone, knows what I am trying to say, as I am having a problem > expressing myself. Obviously a field, I have not studied. > John M. Ross
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