Handsaws are well-established tools for wood processing. Handsaw tooth geometries have customarily been adapted for hand-held electric saws, which utilise higher cutting velocities. Fundamental studies in wood cutting mechanics suggest that a cutting velocity of up to 50 m s−1 has negligible effect on the cutting forces acting on an orthogonal cutting tool. There is a lack of research on the mechanisms involved in the use of native handsaw teeth for wood cutting. This study investigates how cutting velocity affects the forces acting on four bevel-ground cross-cutting teeth extracted from a handsaw blade. Conditioned specimens of Norway spruce [Picea abies (L.) Karst.] were used in the tests. The mean densities of wood specimens were assessed using X-ray computed tomography. Cutting tests were performed on a pre-existing, custom-made cutting-force test machine. Cutting data were collected using piezoelectric dynamometers linked to a data acquisition system. Cutting velocity was controlled by the rotational speed of the arm holding the wood specimen. A customised software application logged and processed the forces acting on the teeth. The results show that the mean resultant force does not vary significantly within a 2.5–15 m s−1 velocity range. The current study suggests that velocity is nearly independent of the system mean cutting force acting on bevelled handsaw teeth cutting across the grain. The findings are particularly relevant for developing cutting tools for wood applications since knowledge from handsaw tooth geometry can be adapted for the design of cutting blades for power tools.
Ej belagd 240315