Plywood Layup Calculator — Custom Plywood Planning

An odd number of layers ensures the grain direction is the same on both face veneers. This creates a balanced panel that resists warping and cupping. Even-numbered panels tend to cup because the grain directions are asymmetric.

Allow 150-200 g/m² of glue per glue line (a panel with N veneers has N-1 glue lines). For interior use, PVA or urea-formaldehyde glues work well; for exterior or marine plywood use a waterproof adhesive such as resorcinol or epoxy. This calculator multiplies your total glue area by 175 g/m² (the mid-point of that range) to estimate the glue mass.

Cold-press pressure for plywood is typically 0.5-1.0 MPa (72.5-145 psi). Softwood veneers need around 0.7 MPa (100 psi); denser hardwood veneers need around 1.2 MPa (175 psi) or more. Use cauls and even clamping to distribute pressure uniformly across the panel. Cold-press PVA/UF glue is then held clamped for roughly 4-6 hours before the panel can be unclamped.