Just thought I'd throw this bit of info into the mix... something that strikes me as an argument in favor of very dried out panels that are kept in dry environments. From Hoadley "The strength of wood increases as the wood gets drier, although the rate of strength improvment is not directly related to the loss of bound water (as is the case with the shrinkage rate) property. For example, maximum crushing strength in compression parallel to the grain and fiber stress at proportional limit in compression perpendicular to the grain is approximatly tripled in drying from green to oven-dry*. Modulus of rupture in bending is more then doubled in the process, but the stiffness in increased by only about half. " *oven dry taken as essentially near 0% MC. The change in strengths are quite dramatic in the range of 25 % MC to oven dry. Static bending about 2 % for 1% change in MC, Compression parallel to the grain about 6% per 1 % change in MC. I surmise from the above quote this is comparable to compression perpendicular to the grain as well. Added to the fact that strength in wood increases with lower temperatures it it would seem that keeping a board dry and cool would insure greatest strength levels over the long term. It also implies that similar levels of compression at different MC and temperature involve quite different abilities of a panel to sustain the degree of compression. Cheers RicB
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