How to Make Plywood
Plywood consists of at least 3 veneers or plies bonded together with an adhesive. Through trial and error, it has become clear that each ply should be oriented with its grain running perpendicular or 90 degrees to the adjoining layer. This has been shown to reduce the shrinkage, bowing, and improve the strength of plywood. Plywood is made out of specially-grown trees that tend to be smaller in diameter than the usual trees to get lumber from. This is not an issue, as the production process involves rotary peeling or sliced veneers resulting in long plies from logs. Rotary peeling involves a massive lathe into which logs are inserted. The lathe sheers off the plies in long sections that can then be glued together to form plywood. Another method is veneer slicing, which looks to be slightly less wasteful than rotary peeling. It involves a similar process to traditional lumber manufacture as the veneer slicing machine slices off the plies. This has been shown to be better for...