Patent ID: 8061938

Claim:
The tip of a generally cylindrical cutting tool used for making a hole within a workpiece, wherein the tip has a central axis and a cutting end and is designed to rotate in a cutting direction, wherein the tip comprises: a) a body having two diametrically opposed flutes with lands therebetween, wherein the lands each have a pair of edges defined as a leading edge and a trailing edge defined by the rotation of the tool; b) a primary margin and a secondary margin spaced apart from one another on each of the lands, wherein the primary margin is adjacent to the leading edge and the margins have the margin diameter along the entire length of the body that is substantially constant; c) a cutting lip extending inwardly from the leading edge of each land to an innermost end; d) a chisel edge defined by a line connecting the innermost end of each cutting lip; e) wherein when viewed along the central axis the chisel edge forms a chisel edge angle with a line extending radially inward from the leading edge of the land to the midpoint of the chisel edge; and f) wherein the chisel edge angle is between 80 degrees and 100 degrees.