Hi JD... this is actually a very interesting point you make here... someone needs to clear this up for me... querie below Now if we imagine one of your structures with a hypothetical board that is truly neutral and passive (not developing any compression or tension) then when you apply the down-bearing of the strings to the bridge, your ribs will be pressed downwards until the compression at the top of the ribs and the tension at the bottom balances the downward force of the strings and the system is in equilibrium. ...... JD What I see here is that in an RC & S board under downbearing load at anything near glue up MC, the ribs will be in the opposite condition with respect to which half of the rib is under compression and which half is under tension then traditional boards. The panels probably reasonably significant compression will be due string load forcing it (and the ribs) down. So the panel will be in somewhat similar condition to compression reliant assemblies... while the ribs will be in opposite orientation. Taking on humidity then... the panel will come under more compression.... and the rib will readily comply since downbearing has loaded it in the aforementioned reverse order of usual... It will as one of the arguements against compression reliant assemblies goes... <<want to straighten out....>> but this time it has the growing compression of the panel working in concert as it were. Strikes me that there are several issues here that haven't been discussed in open forum. Interesting ones at that. Curious also about one thing... how much crown does an RC & S board usually have compared to a typical CC or RC board. Does unloaded crown vary depending on how much compression is designed into the unloaded panel ? Cheers RicB
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