Patent ID: 8177459

Claim:
A ball nose end mill for material removal, the end mill comprising a cylindrical tool body comprising: an axially positioned slot in one end of the tool body, said slot including a locating surface to accurately position a cutting insert mounted in the slot axially and relative to an axial centerline of the tool body; and a fastener for attaching a cutting insert in the slot in a desired position axially and relative to the axial centerline of the tool body; and a cutting insert comprising: a body including two opposed substantially flat retention surfaces, each retention surface including a chip control groove thereon extending from a point at or near an axial center of the body at an angle relative to the axial center of the body; and a peripheral surface joining the two retention surfaces, the peripheral surface including a locating surface at a first end thereof and two arcuate surfaces at an opposed, second end thereof extending rearwardly from approximately the axial center of the second end and positioned on opposite sides of the insert symmetrically with respect to the axial center of the insert, the arcuate surfaces each including an arcuate cutting edge at the intersection of an outer portion of a chip control groove and the arcuate surface, the arcuate surfaces being formed with a face clearance angle under the cutting edges.