Drying timber warping preventing structure - uses inserts less affected by moisture alteration than main portion in sap wood side

摘要

The structure prevents warping of sawn timber at right angles to the grain when drying, with one face (2) formed by the heartwood and the opposite one (3) by the sapwood. One or more inserts (10) are set in the timber at the sapwood side, with their thickness (M) and width being appreciably less than those (H, D) of the timber itself. They extend for the full length of the timber in the direction of the grain. In the transverse direction of the timber and at right angles to its grain the alteration in dimensions of the inserts, due to variation in the moisture content, is considerably less than that taking place in the timber for the same reason. ADVANTAGE - Warping prevention, less waste during planning, and plank stiffening.