Cutting insert with chip control

Abstract From the Canadian patent

A cutting tool for improved chip forming material removal efficiency over a wide mid-range of typically used feed rates and depths of cut is disclosed in a preferred form of an indexable polygonal cutting insert. A first chip control groove of uniform width and cross section radius extends from a cutting edge at each side of the polygon and terminates inwardly from the edge in a second chip control groove having a cross section of larger radius but of lesser depth than that of the first chip control groove. The second groove has its largest width at a point substantially midway between adjacent cutting corners of the polygon and diminishes to zero width at the end of each straight cutting …