아까시材의 天然乾燥

Air-drying of black locust

Two stacks of 25 mm thick black locust boards were air-dried during summer in Daejeon. Boards were stacked with conventional stickers and moisture pallets made of plywoods and stickers. In early stage the drying rates of the moisture pallet stack were lower than those of the sticker stack. but after 90 days the moisture content difference between two stacks was only 0.8 %. It implies that the moisture pallet stacking is effective to reduce surface checking usually occurring at the beginning of drying. but unfortunately which hasn’t been proven with thin black locust boards of 25mm thick. Number of the boards with end checks in the sticker stack were twice as many as in the moisture pallet stack. Steady-state moisture diffusion coefficient of 15mm thick black locust boards were measured by vapormeter cup method and compared with those of white oak. Steady-state diffusion coefficient of black locust in radial direction is cose to that in tangential direction. while those values are. respectively, 1/7 and 1/4 of oak ’ s.