We assessed the quality of beech sawn timber before and after the normaltemperature convective kiln drying. Dimensions at freshly sawn boards were measured and the number and size of surface cracks and fissures on knots were determined. The grain direction and orientation were additionally determined at boards as well as the proportion of the discoloured wood. Boards were according to the above criteria ranked by quality using the directive of the European organisation for the sawmill industry (EOS). After the 15-day standard industrial drying procedure (Tmax = 38 °C) to a final 18 % wood moisture content the measurements were repeated. We have found greater reduction of utilisation rate, when boards of lower quality are dried. The resultant differences have contributed most by surface cracks and fissures close to knots. After drying, 8 % and 15 % of the boards in the A- and B-grade should be classified to the lowest C-class.
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