Patent ID: 8202026

Claim:
A cutting insert ( 10 ) comprising: a front surface ( 20 ) extending between an upper surface ( 12 ), a lower surface ( 14 ) and two side surfaces ( 24 ) that extend between the upper surface ( 12 ) and the lower surface ( 14 ), the upper surface ( 12 ) joining each of the side surfaces ( 24 ) through a corner surface ( 16 ) at each side of the upper surface ( 12 ); a main cutting edge ( 32 ) associated with the upper surface ( 12 ) formed at the intersection of the front surface ( 20 ) with the upper surface ( 12 ), auxiliary cutting edges ( 34 ) formed at the intersection of the front surface ( 20 ) with each of the side surfaces ( 24 ); and corner cutting edges ( 36 ) formed at the intersection of the front surface ( 20 ) with each of the corner surfaces ( 16 ); wherein: the main cutting edge ( 32 ), the auxiliary cutting edges ( 34 ) and the corner cutting edges ( 36 ) have a rake surface ( 38 ) associated therewith in the front surface ( 20 ); a front portion ( 46 ) of the upper surface ( 12 ) extends rearwardly from the main cutting edge ( 32 ) and upwardly toward a central portion ( 48 ) of the upper surface ( 12 ) as seen in a side view of the cutting insert ( 10 ); the main cutting edge ( 32 ) is curved and slopes downwardly toward each of the auxiliary cutting edges ( 34 ) as seen in a front view of the cutting insert ( 10 ); the main cutting edge ( 32 ) slopes inwardly and rearwardly from the corner cutting edges ( 36 ) as seen in a top view of the cutting insert ( 10 ); and the entire length of the main cutting edge ( 32 ) lies on a cylindrical surface.