Abstract: A tooling insert for a screw machine includes a plurality of cutoff blades. The insert is indexable. The cutting side of the blade includes a planar impact surface with a 7° side rake angle. In addition, the blade cutting side has a narrow raised land adjacent the impact surface.

Abstract: A tool holder for a resharpenable cutting tool insert has a body portion which includes a recess. A wedge member is positioned in the recess. A locking screw locks the wedge member such that the top surface of the wedge member is in engagement with the bottom surface of the insert and the locking screw is threadably connected to the body portion and to the wedge member so that the cutting tool insert may be removed for sharpening and re-inserted at the same location relative to the tool holder.

Abstract: A spot drilling tool includes a drill holder and an insert removably mounted to the holder. The insert is a standardized part configured to support a drill point in a predetermined position forward of the drill holder and centered on the rotational axis of the drill holder. The drill point has two flutes and two substantially conical land surfaces extending between the flutes. The land surfaces have centers of curvature offset from the rotational axis of the insert to provide radial clearance for the trailing portion of the land. A chisel edge at the tip of the drill point is supported by a tapered web defined between the diagonally opposed and offset flutes. Linear cutting edges are formed at the junction of a planar flute surface and the conical land surface. The cutting edges define a narrow included point angle of between 50° and 80°.

Abstract: A self-calibrating countersink tool includes a reusable insert-holder with an axis-defining shank portion and an insert-receiving notch disposed at one end of the holder. The tool also includes at least one selectively attachable insert which is sized and shaped to be received within the insert-receiving notch of the holder. Each disposable insert includes a tapered cutting-edge portion and a notch-mating portion which is complementary in shape to the insert-receiving notch. When the insert is in mating engagement with the holder, the cutting-edge of the insert is disposed forwardly of the holder and defines an angle of between about 105 and 165 degrees relative to the holder axis. The countersink tool also includes an affixation means for affixing a disposable insert to the holder such that the insert is in mating engagement with the insert-receiving notch.