>If you take an unribbed panel, and dry it out to the extremes of 4% MC, >and then constrain its dimensions at that so that it is not allowed to >expand either outwards, or upwards or in any fashion and bring the MC up >to 13 % the panel will get pretty severely compressed... yes ?... ok.. >If you allow this to sit over enough time that if in releasing the >constraints the panel simply retains the dimensions it had under >constrainment.... then what happens to the size of this panel if you >dry it down to 4 % again ? You've seen the answer to this question in a lot of pianos. It will shrink, but not nearly as much as an un-crushed panel would. If the panel didn't still shrink after being crushed and damaged by restraint under expansion, it wouldn't ever crack. Ron N
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