Patent ID: 7575401

Claim:
A drill for producing holes in composite materials comprising: an elongate, tungsten carbide drill body including a helical flute and a polycrystalline diamond cutting tip, the cutting tip further comprising: a center point coaxial with a longitudinal axis of the drill body; a primary cutting lip extending from the center point toward an outer diameter of the drill body, the primary cutting lip extends from the center point toward the outer diameter at an angle of from about 45° to about 75° relative to the longitudinal axis of the drill body; and a shear cutting lip extending from the primary cutting lip to the outer diameter of the drill body, the shear cutting lip having a positive rake face angle intersecting with a positive primary relief angle and being oriented at an angle of less than or equal to about 15° relative to the longitudinal axis of the drill body to create a sharp shearing edge.