> Ron, Barbara > Although I'm* not* a compression crowned soundboard builder I have > built many boards with many kinds of spruce & grain oreintations. Even > pressing ribs on at 5.5 to 6.% compression still exsist in the panel. If > I'm sending a board to the desert it gets dried a bit more. If the Bay > area less is fine. Hi Dale, While you're certainly not building compression crowned soundboards, you are building partially compression supported boards. The ribs are doing part of the work in supporting bearing, and the panel is doing the rest, since the number and dimensioning of the ribs couldn't support crown without panel compression. Nothing wrong with that when it comes to making music, as you have seen and heard for yourself, but denser grain does work better and more dependably in this type of construction. An RC&S board does very nicely with 8-12 grains per inch and no, they don't seem to be as reactive to humidity changes as either CC or RC boards because the panel isn't doing much with compression in the first place. I don't know how the Seiler is ribbed, so I can't say how the low grain density panel reacts. ??? Ron N
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