Abstract: A cutting tool insert having a controlled contact clearance behind the cutting edge which limits flank wear and allows more coolant near the cutting edge further allowing an increase in surface speed, feed rates, and tool life. The controlled contact clearance surface provides a first wear zone and a second wear zone, the first wear zone generated during operation of the drill insert allows the flank wear distance to grow from zero to the distance from the cutting edge to the controlled contact clearance surface, the second wear zone keeps the flank wear distance substantially constant until the controlled contact clearance surface is substantially worn away.

Abstract: The present invention provides a new drilling tool useful in machining hydraulic port seals for fluid power ports. The drilling tool drills the port hole to size in a solid material for the minor thread diameter in combination with forming the port in a single operation. The drilling tool has a tool holder having a rotational axis, a first drilling insert having cutting surfaces on a first side and a mounting surface on a second side, at least one second drilling insert having a predetermined cutting surface portion and a mounting portion which is mounted on the holder at a location from the rotational axis of the holder. The at least one second drilling insert has first and second portions which engage and machine a work piece in a drilling operation to form a spot face and a seal form.

Abstract: The present invention is a drilling system for cutting flat bottomed holes in work pieces. The tool has two opposing angled cutting edges extending from a rotational axis, with the inner portions of these cutting edges extending upwardly to create an overlapping web at the center. The overlapping web strengthens the center portion of the cuttings edges of the tool. The angle at which the inner portion of the cutting edge is inclined can be increased to create a center point on the cutting surface of the tool. The center point adds stability to the tool as it rotates along its longitudinal axis. The cutting edge has a rake surface with a positive rake angle that lessens the forces on the insert and also allows for better formation of chips of stock material being removed. Chip breakers can be cut into the cutting edges of the insert, further aiding in the removal of stock material.