REAMER Russian patent published in 1999 - IPC

FIELD: tools for finishing surfaces of openings. SUBSTANCE: reamer includes at least one cutting tip and two guiding plates. Cutting tip has at least one main cutting edge and adjoining to it side-cutting edge. In zone of main and side cutting edges back surface is arranged. Back surface has near side-cutting edge first zone with back angle equal approximately to 7 degrees. Near side-cutting edge there is second zone of back surface adjoining directly to side-cutting edge, extending to first zone of back surface and having back angle significantly less than that of first zone of back surface. EFFECT: elimination of defects caused by initial wear. 7 cl, 8 dwg