The top is braced and glued to the rims (prior to attaching the back).

I tested the deflection under 10, 20, 30, and 40 lb of weight, applied directly over the bridge.

Then I strung it up and rechecked the deflection.

My 11 gauge strings pull at @ 142 lb, and my break angle is 12 degrees.

If the formula I'm using is correct:

- string_tension x 2 x sin((break_angle x (3.14/180))/2)

But the top is deflecting as if there were only @ 20 lbs of downward force being applied.

Is my formula off somehow? It's been so long now that I forget where I got it from.