>David, > >Bravo! Well said! Yeah for simplicity! Ron, Brian T., Delwin, didn't he summed it up in laymen's terms? * Didn't I respond to his post? Didn't I say yes? <G> Well here's another one for him, and you too... yes, and yes. >Frank, I think David nailed it. Unlike your yardstick analogy, no one is grabbing the ends of the soundboard and artificially "forcing" an arch. In a compression crown, the arch is created by internal forces (increased water content) pressing outward against the cell walls (COMPRESSION). The rib is simply limiting the GROWTH of the underside at a greater rate than the growth on the topside. Even though ALL of the cells are GROWING, the arch is created only because the top of the soundboard is GROWING with less resistance because the rib is on the bottom. > >Did I get it right? * Absolutely, er, yes. >As to rib-crowning. Don't think of it as the rib "forcing" the board to arch as in Frank's yardstick analogy. Rib crowned boards are still dried before ribs are glued on right? Just not as much. If this is the case, once humidity is re-introduced to the cells, then think of tapered rib as "following" the board, and not "fighting" it like a straight rib does. > >I'm not an expert either. To quote you, David, "I'm learning, not teaching." Hopefully though, I've figured this out finally. > >Cheers, >Brian Henselman,RPT * That's it, you're hired! Ron N
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