Time-Based Kiln Drying Schedule for Sugar Maple for Structural Uses

Abstract

A previous study (Simpson and others 1998) showed that maple could be kiln dried successfully for structural uses by a schedule that was accelerated in comparison with the traditional maple schedule intended for products where appearance is important, such as furniture. In addition to being unnecessarily conservative and slow for lumber intended for structural uses, the traditional maple schedule is controlled on the basis of moisture content. Changes in kiln conditions are made when the lumber reaches certain levels of moisture content; this requires some method of estimating moisture content during the kiln run. Because of the less exacting quality requirements of structural lumber compared to appearance-grade lumber, traditional kiln schedules for softwood structural lumber are usually based on time; that is, changes in kiln conditions are made at predetermined time intervals rather than at predetermined moisture content levels. Thus, periodic estimates of moisture content during the kiln run are not necessary, and time-based schedules are therefore more efficient than are schedules based on moisture content.

Citation

Simpson, Wiliam T; Wang, Xiping. 2001. Time-Based Kiln Drying Schedule for Sugar Maple for Structural Uses. USDA Forest Service, Forest Products Laboratory, Research Note, FPL-RN-0279, 2001; 6 p.