Abstract: The cutting insert disclosed is a block of hard metal configured on at least one of its major faces to provide peripheral cutting edges successively index able about a central fastener location to position each edge serial for cutting. The major face slopes downwardly and inwardly from the cutting edges to provide rake surfaces of positive rake behind the cutting edges, and then rises as a sloping ledge to a central boss. A series of depressions disposed along the rake surface produce a ribbed chip which breaks more readily, and into smaller chips, easier to flush or otherwise remove from the cutting site.

Abstract: A high-speed end-milling router for ramping entry into a workpiece has plate-like hard metal cutting inserts fitted in pockets milled in chip gullet surfaces to present the insert at a desired axial rake angle and with radially inwardly and outwardly facing cutting edges. Each insert is secured in its pocket by two countersink headed machine screws whose holding power against centrifugal dislodgement of the insert is reinforced by an interfitting boss integral with and upstanding from the seating surface of the pocket extending into a blind recess molded in the undersurface of the insert.

Abstract: A generally cylindrical drill, particularly an insert drill having multiple cutting inserts, helical chip grooves to clear the chips from the hole, and a gripping shank opposite the cutting end of the drill, wherein the drill experiences an unbalanced resultant transverse force upon the cutting tip of the drill, and that resultant is oriented perpendicularly to an axial plane containing the neutral axis of the maximum resistive moment at the grooved section of maximum bending stress adjacent to its juncture with the gripping shank.

Abstract: The specification and drawings describe and show a thread-rolling die whose thread-forming lands are modified at their points of emergence along the side edge of die so that the crest of the ramp formed by the emerging end of the land remains parallel to the crest of the adjacent land.

Abstract: A high-speed end-milling router for ramping entry into a workpiece has plate-like hard metal cutting inserts fitted in pockets milled in chip gullet surfaces to present the insert at a desired axial rake angle and with radially inwardly and outwardly facing cutting edges. Each insert is secured in its pocket by two countersink headed machine screws whose holding power against centrifugal dislodgement of the insert is reinforced by a projection from the seating surface of the pocket extending into a blind recess molded in the undersurface of the insert.

Abstract: The cutting inserts of this patent are provided with positive cutting geometry and are especially adapted for service in face milling and shoulder milling raw castings and other hard-shelled workpieces by providing a cutting edge land which varies in width along the cut from narrowest at the bottom of the main cutting edge to broadest where the cutting edge meets the hard surface of the workpiece. In double-ended cutting edges, i.e., where the cutting edge is designed to cut equally in cutters of either hand of rotation, the maximum land width occurs at cutting edge midpoint and tapers to minimum width at each end. The surface of the land may also desirably be warped, twisting from radially positive rake at the bottom of the main cutting edge to neutral or even negative radial rake where the cutting edge meets the hard surface of the workpiece.

Abstract: A plunge milling cutter is shown which displays an unusually high cutting edge density with positive cutting geometry derived from the configuration of the rake surfaces of its hard metal cutting inserts, notwithstanding their generally parallelepiped form.

Abstract: The cutter includes a plurality of on-edge indexable cutting inserts comprising two parallel major plane surfaces and two opposed plane parallel minor edge surfaces serving respectively as clearance and cutting face surfaces. The minor edge surfaces having a pair of grooves parallel to the major surfaces and having a plane mid-portion and the major plane surfaces have thereon adjacent to each of said minor edge surfaces a narrow land intersecting the adjacent groove of the adjacent minor edge surface at an acute angle, to form therewith straight and parallel cutting edges.

Abstract: Shown and described is an on-edge cutting insert for milling cutters in the form of a flat six-sided block having two parallel major faces which are seating and clearance faces, and two opposed edge surfaces which are rake faces which intersect at least one major face of the flat block to form two parallel cutting edges therewith, and two other opposed edge surfaces which are recessed centrally of their major dimension to form sideward projections of the cutting edges at the corners of the major faces.The recesses accommodate the sideward projections of the cutting edges of the adjacent inserts in an interfitting array of inserts along a single chip gullet in which the several inserts sweep contiguous concentric segments of a more extensive uninterrupted cutting path.

Abstract: A replaceable on-edge cutting insert is especially adapted for use in end-milling cutters of small diameter, viz., in the size range down to one-half inch in diameter, and with cutting geometry which positions the rake face of the insert in the cutter body with substantially neutral radial rake and positive axial rake. A modified form having a cylindrical primary clearance land is used in the tip cutting positions of a ballnose end mill.

Abstract: The clamping mechanism and companion cutting insert disclosed are designed for use in a milling cutter intended to be ganged with other like cutters on a common rotational axis for the simultaneous milling of multiple slots or grooves. The axially movable clamp for the on-edge inserts employed in the cutter is operated indirectly by an adjusting screw accessible radially from the outside of the ganged cutter bodies without requiring disassembly of the individual cutters to index or replace the cutting inserts. In each of several clamping mechanisms disclosed, the ultimate clamping element or detent takes the form of an arm which is rocked into engagement with the insert at the site of a blind depression in the face of the insert, being drawn in the axial direction by inward adjustment of a radially accessible adjusting screw, and rockable in the reverse direction by a return spring to release the insert as the adjusting screw is backed off.

Abstract: Thread-cutting apparatus includes an indexable insert having multiple thread-cutting profiles. The invention may be embodied either in a thread-milling insert or a thread-chasing insert. The insert is configured to provide clearance for internal threading and to enable cutting force to be directed through a large cross-sectional area of the insert.

Abstract: An indexable face-milling insert having eight compound cutting edges of the same hand, each having an included angle of 90.degree. over its entire length which comprises two straight segments at right angles to each other and an intermediate bevel cutting portion.

Abstract: A ballnose end mill with identical on-edge convex inserts is capable of drilling and milling, and apportioning the major milling load between the inserts.

Abstract: Thread-cutting apparatus includes an indexable insert having multiple thread-cutting profiles. The invention may be embodied either in a thread-milling insert or a thread-chasing insert. The insert is configured to provide clearance for internal threading and to enable cutting force to be directed through a large cross-sectional area of the insert.