Ah but it is another matter. The RB&S board will by its design nature maintain a more stable stiffness to mass relationship with variances in RH, and the CC board will vary more across the grain with those same variances. RicB >/ but achieving that and at the same time the same stiffness to mass />/relationships is another matter. / It is not a 'another matter'. If you have determined a certain spring rate but would like more mass you can use more, lower and wider ribs, and your mass will be increased at a given stiffness. If you want less mass for the same stiffness (spring rate) you can use less, deeper and narrower ribs. Its a simple matter to arrive at the spring rate and mass relationship required, using RC construction. Furthermore, I believe that the stiffness of ribs should ideally be varied along their length. The rib should be stiffer under the bridges (where most CC boards collapse in short order), getting gradually weaker as we move from the bridges to the ends of the rib. The tapering of rib strength is a cake walk when building an RC& S board. While the CC building school can contour the panel thickness to increase the stiffness under the bridges, it is more of a 'blunt instrument'.
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