Influence of regeneration process parameters on geometry and defects of clearance surface of planer knives used in wood planing process

Abstract

AbstractA properly implemented strategy regarding the planer knife regeneration process, may not only restore the original cutting ability of the tool, but even increase its operational quality, including its durability for industrial woodworking processes. This article presents experimental results and discussion in respect of sharpening planer knives with cubic boron nitride grinding wheels. Both the grinding conditions and machining surface quality were analyzed. Application of improper size or loads of abrasive grains may lead to the appearance of grinding burns on a machined surface, or result in a surface with cracks and grooves. The results of the measurements carried out indicate that surfaces with reduced values of roughness and waviness parameters can be obtained, even up to 22% (as in the case of the reduced peak height parameter, Spk) in relation to new knives, prepared at a factory. The value of St and Sds parameters are almost the same as reference knife (deviation up to 3%). Due to machining marks, the total waviness exceeds 33%. Our research also shows that due to the technological quality of the knife surfaces, it is beneficial to use CBN grains with a low depth of cut (ae no more than 0.02 mm), but a moderate or high feed rate (the best choice is about 470 mm/min for vft). Presented results constitute an important know-how for the grinding process with the use of grinders used by operators (like WEINIG Rondamat 980) during the sharpening of planer cutter heads in the wood industry.