Ah makes more sense now, thanks for the explanation. I'm an undergrad in EE so mechanics is not my strong point. So a planar face of a cube cannot satisfy the

Ah makes more sense now, thanks for the explanation. I'm an undergrad in EE so mechanics is not my strong point. So a planar face of a cube cannot satisfy the equilibrium equations? Interesting ... so then a cube will necessarily bulge so the radius is enough to satisfy the equations, right?