How to understand the principle of symmetry of exterior plywood

The exterior plywood has great strength and excellent toughness, and the medium density fiberboard material is relatively uniform and suitable for processing. It is a three-layer or multi-layered plate-like material which is formed by cutting a wooden section into a veneer or by cutting into a thin wood by wood, and then bonding with an adhesive, usually using odd-numbered veneers and making adjacent veneers The fiber directions are glued to each other vertically.

Then, the so-called outdoor plywood symmetry principle is: if there are two symmetrical positions of the single chip, it may be made by the same method, and the fiber directions are parallel. No matter which symmetry center the distances are equal, and the type of wood is the same, the thickness is the same.

If the center of the central chip of the veneer coincides with the center of symmetry of the plywood, the number of chips in the plywood should be an odd number. The outdoor plywood has a cross section on both sides, and the number of chips on both sides of the symmetrical center is the same, and the symmetrical position of the slabs is also equal.