> > Hey somedays I can't string two cohesive thoughts together. I know > what I'm talking about but I'll be darned if anybody else can figure it out. How's that again???? <G> > > You're >> >> still talking about something like 0.003" rim spread from full crown to >> flat. > > > Dale wrote > >>>>I'm not sure I agree with that. I'm about to press up an Stwy L board > and after it's pressed and crowned I'll measure across the bottom from each > end of the longest rib and then I personally will sit or stand on the board > on the floor and see how far the rib dimesion expands. Hmm this might be hard > to measure but I'm going to try anyway. Maybe I'l just make a mark on the > floor at each rib end and visually observe. Ever done this? It seems to me > that .003 figure would have to be greater for the crown to completely > col.lapse > Actually I see your point thought that even if the board/ribs were pressing > significantly into the rim like a buttress the wood creep in the rim over > time would still eventually be the crowns undoing. Still it seems like it > would have to spread at least .050. Do the math. It's not as much fun as jumping on new soundboards, but it's easier to explain if someone catches you at it. In Excel: =DEGREES(ASIN(chord/(radius*2)))*2 Chord being the rib length, gives you the segment angle in degrees. =(PI()*(radius*2))*(angle/360) Gives you the arc segment length. Compare it to the chord. Ponder. Scratch head. Scary, ain't it? > >> >> Exactly the point. > > > >>>>>>>>Hey I catch on quick after a long time. > >>>>>>>>>Dale>>>>>>>> Simple as chickens. You knew it all along. Just have to figure out how to describe it to one another. Ron N
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