
First steps for me is to test the wood to determine a target thickness. I have 2 methods. The first method uses tap frequencies to determine the Young's modulus (stiffness). This method works great but it requires that plate tested is rectangular and uniform thickness. The top plates I had allowed me to do this test. It is easier to show rather than tell so here is a video of me testing the top plate.
The back plates were more trapezoidal so I determined the long and cross grain Young's modules using rectangular pieces from the area outside the profile of the guitar by performing a deflection test.
