----- Original Message ----- From: "Richard Brekne" <Richard.Brekne@grieg.uib.no> To: "Pianotech" <pianotech@ptg.org> Sent: August 28, 2003 2:11 PM Subject: Re: Compression Question > > Its like you can > hypothetically speaking squezze the thing down next to nothing and it will > still shrink that 1-1.5 % given a drop 8 % drop in EMC. No, it's not like that at all. There are physical limits to everything. Long before you squeeze the thing down to next to nothing you will have...well, next to nothing. You certainly won't have anything remotely still resembling wood. The compression ridges that develop in some soundboards are the result of the wood fibers in that part of the panel (specifically in the earlywood portion of the annular rings) being squeezed beyond their physical limits. They compress without catastrophic failure up to the point of their elastic limit, then structurally fail. That part of the panel, then, no longer follows the normal rules of expansion (or compression) and contraction (or tension). Del
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