Moisture Variations in Dried Hardwood Timber
This project investigated why moisture gradients occur in Australian hardwoods during drying and their affects on the performance of timber in service; and aimed to improve existing technology(ies) and/or processes to reduce moisture content variability between and within boards.
The first part of the project involved milling a large number of boards and assessing their moisture content during a strict drying regime. The results showed there was no timber with undesirable final dry moisture contents. This suggests that moisture content problems caused by variations in timber properties may only be partly true. Kiln performance and drying practice may also be factors causing the reported problem.
The second part of the study randomly selected dried stock at various industrial hardwood sawmills to determine the extent of the problem. This survey did show problems with moisture content. This may be caused by relying on MC resistance probes instead of using sample boards; incorrect use and/or using uncorrected moisture content readings of moisture meters; relying on time based drying schedules; kiln limitations; and storing material in wet climatic conditions after drying.