The plywood is made of 3 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. 4mm Laser Safe Birch Plywood B/BB. A 500x300mm format for laser cutting 4mm B/BB, cut with a saw made of 4mm dry-resistant birch plywood, B/BB, with an accuracy of +/- 2%.
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