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Wood processing industries have continuously developed and improved technologies and processes to transform wood to obtain better final product quality and thus increase profits. Abrasive machining is one of the most important of these processes and therefore merits special attention and study. The objective of this work was to evaluate and demonstrate a process monitoring system for use in the abrasive machining of wood and wood based products. The system developed increases the life of the belt by detecting (using process monitoring sensors) and removing (by cleaning) the abrasive loading during the machining process. This study focused on abrasive belt machining processes and included substantial background work, which provided a solid base for understanding the behavior of the abrasive, and the different ways that the abrasive machining process can be monitored. In addition, the background research showed that abrasive belts can effectively be cleaned by the appropriate cleaning technique. The process monitoring system developed included acoustic emission sensors which tended to be sensitive to belt wear, as well as platen vibration, but not loading, and optical sensors which were sensitive to abrasive loading.

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Wood fiber–plastic composite materials, a relatively new material, are finding applications mainly in the US residential and commercial construction markets. Thus, the volume of material produced and used is steadily increasing while the range of applications keeps expanding. So far, attention has been paid mainly to primary production processes of wood fiber–plastic materials, while secondary manufacturing processes have attracted less attention. However, with the broadening applications of such materials and their increasing use, secondary manufacturing processes for wood fiber–plastic materials are gaining importance. This study investigated the performance of five commercially available wood fiber–plastic composite materials and solid wood (eastern white pine) with respect to tool wear and resulting material surface roughness. Large performance differences between different wood fiber–plastic composite materials and between solid wood and wood fiber–plastic composite materials with respect to tool wear were found. Solid wood did wear the exchangeable tungsten carbide knives with a standard cobalt binder and ultrafine carbide grain knives used for the tests 12 to 42 times less than the wood fiber–plastic composite materials. However, some wood fiber–plastic materials were found to have a smoother surface than solid wood after 38.2 m of cutting. As this research showed, different wood fiber–plastic composite formulations behave differently when subjected to secondary manufacturing processes, and more research is needed to better understand the underlying causes for those observations.