Originally Posted by Stillraining
isn't there is a huge storage facility for aircraft in the desert where the humidity stays around 10 %? also in furniture building you want your wood well below that level even so I fail to see how this would hurt a thing..Ill gander a guess that the wood used in boat construction is below 7% moisture content..IMHO
Uh ... ambient relative humidity is different from MC of interior woodwork. Which is measured as percentage by weight
. All that cellulose to deal with, you know. Hardwoods are air-dried from 25-35% MC (full saturation) to around 15-18%; often (tho not always) they are then kiln-dried to 6-8% MC. That drives off all the free and some of the bound water. Here in the desert, it stays there more or less year round; in damper climates, wood will creep back up toward 15%. In difficult climates, like Michigan or West Texas, MC of interior woodwork will fluctuate between 6 and 12% on a six month sine wave, driven by but lagging a few months behind ambient humidity. That's a real bastard to cope with. That's the sort of long-period, large amplitude swing I'm warning Faster to avoid.
Certain woods, like mahoganies (true and Phillipine), don't much care. They have low absolute movement and low T/R ratios (tangential to radial movement). Other woods like maple or beech are high in both and are likely to distort if subjected to large changes in ambient humidity. Wood-veneered panel products can be exceptionally damage prone,
as the veneer is thin and highly stressed during the manufacturing process; it is then bonded with inelastic glue (typically urea resin) to a core that may have very different movement properties. The result of multiple large moisture cycles can be severe surface checking or even failure of the glue bond.
of the environment is more important than damp vs dry climate. Actually, the very finest woodworking belongs to Japan, in part because it is cool and damp there year round. Highly conducive to fine assemblies using air-dried woods.