BALANCED DRILL WITH CENTER CUTTING ACTION

摘要

BALANCED DRILL WITH CENTER CUTTING ACTION A drill is provided having opposed primary and Secondary cutting edges. The primary cutting is disposed at an angle less than ninety degrees to the longitudinal axis of the drill. The primary cutting edge extends across the longitudinal axis of the drill to a terminus intermediate the longitudinal axis and the periphery of the drill. The secondary cutting edge extends inwardly from the periphery of the drill to a point intermediate the periphery and the longitudinal axis of the drill. The primary and secondary cutting edges are spaced from one another along the longitudinal axis so that the end of the primary cutting edge nearest the longitudinal axis leads the drill into a workpiece. The primary cutting edge drills the inner part of the hole and the secondary cutting edge drills the outer part of the hole. The primary and secondary cutting edges are designed to generate substantially balanced forces about the longitudinal axis of the drill. Flutes extend from each cutting edge for efficient and reliable removal of chips.