A 500x300mm format for laser cutting 3mm,4mm or 5mm B/BB, cut with a saw made of 3mm dry-resistant birch plywood, B/BB. May have oval inserts on BB side. The plywood is made of 3(3mm and 4mm) or 5(5mm) layers of Baltic birch, the stresses in the board will warp or twist the board, if you need a perfectly flat, do not make the plywood.
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