Patent ID: 6848869

Claim:
A drill insert comprising: a drill insert body having at least a first end opposite a second end and a first face side opposite a second face side; wherein the first end of the drill insert body is a generally planar surface and the second end has at least two main cutting edges formed thereon at a first inclusive angle, a web formed between the two main cutting edges, and a web thinning notch formed on either side of the web, forming web thinning cutting edges at a second inclusive angle and separated from each other by a chisel; wherein the second inclusive angle is larger than the first inclusive angle; wherein the chisel is formed by the intersection of at least a primary web thin clearance surface behind each web thinning cutting edge; wherein the primary web thin clearance surface is formed at a primary web thin clearance angle with respect to a projected plane normal to a plane through the web thin cutting edge, wherein the plane through the web thin cutting edge is parallel to the longitudinal axis of the insert, wherein the projected plane is tangent to the web thin cutting edge.