Aperture geometry: area, wall contact and depthIdeal straight walls; diagram not to scale. Surface condition and paste behavior are not simulated.Aperture geometry: area, wall contact and depthLWTop view: opening area A = L × WtArea ratio = A / (P × t)Rectangle P = 2(L + W)Circle area ratio = D / (4t)Ideal straight walls; diagram not to scale. Surface condition and paste behavior are not simulated.