The role of tool composition and tool geometry in controlling the surface finish in machining wood

An examination of several brazed cemented carbide tool inserts that were used in service for cutting cured (dry) pine is described. A laboratory test is also described where the relative resistance to chipping of the brazed tool inserts was measured.It is shown that tool wear occurs through a continuous increase in the tool cutting edge radius that produces a deterioration in the appearance of the machined surface. It is also shown that an increase in either the binder volume fraction or the tool wedge angle produces an increase in the energy absorbed on impact. It is suggested that if progressive wear determines the useful life of a cemented carbide cutting tool then a low volume fraction of binder is required whereas if tool edge chipping determines the useful life of a cutting tool then a large volume fraction of binder and a large tool wedge angle are required.