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Anyone deflection test their backs? If so what sort of readings do you aim for on a finger-picking, flat picking or all rounder steel string?

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Formerly JJH

I learn more from my mistakes than my successes

I do deflection testing of backs along with my tops and lacking a specific starting place for the back, I make them deflect the same as the top. This results in a fairly thin back plate of about .070" which then gets stiffened up with a lattice bracing system.

My feeling is that deflection testing on the top makes a lot of sense, but I'm not sure if the same is true for the back. On the top you need to worry about having enough stiffness to withstand the bridge torque, and that's what delection testing can tell you. The back has a different job. I keep track of the back's resonant modes, but don't worry too much about the deflection numbers. Of course, you can't let it get _too_ thin...