>1. Is it not increasingly difficult to bring wood from, say, 6.0% to 4.0% >MC, than it is to get it to the initial 6.0%? (Recognizing that the lower >the MC, the more unstable the material becomes, until one ends up working >with dust). * Don't really know. >2. Does component handling and assembly timing not become even more >critical at lower MC's? * It seems like it should be, because panel expansion is so much more critical in compression crowned boards, but I suppose it depends on the difference between the MC of the hot box, and the MC of the assembly area. The closer they are, one to the other, the less critical it would be in either case. >3. If a panel is pressed, by whatever means, to a radius of 60', would the >"net" radius be more on the order of 56' or so? Regardless of the net >value, I must assume it can be calculated somehow to be repeatable. * It depends on the rib stiffness, and which type of crowning system you're using. You likely would end up with a slightly, to substantially tighter radius than the press caul depending on how far you dried the panel down. If the board were assembled with panel and ribs at ambient room MC, the resultant crown would be a greater than 60' radius. >4. What happens if, for whatever reason, the ribs and panel are not in >equilibrium with each other at the time of gluing/pressing? IOW, consider >that they came from two different hot boxes. * Since wood doesn't change dimension all that much parallel to the long grain, it shouldn't make any difference at all. >5. How does a heat table relate to a hot box, and the respective virtues of >either? * Don't know, no experience. >If I can't participate in the answers, at least I can stir the pot of >confusion! <g> > >Jim Harvey, RPT * Welcome! Gotta go. It's thundering, and the radar indicates that we may get sucked up into the sky in about ten minutes. Wish me luck. Ron N
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