I think the point being raised boiled basically down to the degree of compression an RC & S board experiences when string bearing leaves whatever residual crown ends up being the case. I'm not sure thats been quantified by anyone yet... so it might be a nice thing for someone to throw into the mix. Leaving 25 % or original crown strikes me as introducing fairly significant amounts of compression into the panel. Cheers RicB While there are different approaches by those doing rib crowned boards, it's not unusual to design them so that there is only about 25% of the original crown remaining after they are loaded.
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