Influence of the shape of the knife’s cutting edge on the cutting force in the chipless cutting of three tree species

This article presents results obtained for the chipless cutting of wood using different cutting heads. Wood processing in forestry and the demand for firewood are currently increasing, so it is necessary to apply appropriate tools to the existing process, which will be sufficient for fast and high-quality operations. Four groups of cutting knives were used for experimental measurements, where the influence of the cutting knife edge on the cutting process was determined. The cutting knives were always made of the same material and with the same blade angle ∢ 30°. Measurements were made on spruce (Picea abies), beech (Fagus sylvatica), and willow (Salix caprea) trees. The size of the Fc cutting force was selected as the monitored variable, and then the dependent factors (kind of wood, wood diameter, cutting knife) were monitored in terms of their influence on the size of this Fc cutting force and thus also on the energy consumption. Based on the statistical evaluation, the most suitable shape of the cutting edge of the knife was selected, with this shape of the cutting edge, a reduction in the cutting force Fc was achieved for selected woods.