The technical problem to be solved by the present disclosure is to provide a single-sided high feed cutting insert which can have increased edge strength and reduced cutting load so as to be suitable for high feed machining. To this end, the single-sided high feed cutting insert of the present disclosure comprises: a short cutting edge disposed between a major surface and a short lateral surface; a long cutting edge disposed between the major surface and a long lateral surface; and a corner cutting edge disposed between the short cutting edge and the long cutting edge, wherein the short cutting edge has an outwardly convex curved shape when viewed from the major surface, and a minor surface has a straight shape when viewed from the short and long lateral surfaces, respectively.

It is an object of the present invention to provide a rotary cutting tool that can divide chips at an appropriate size, suppress the incidence of edge chipping and damage attributed to chips to the cutting tool and a workpiece, extend the tool service life with regard to the machining of hard, brittle materials, and improve machining efficiency. The rotary cutting tool includes a hard coat film 3 coated onto a tip end section of a tool body 1 having a chip discharge groove 2. A rake face 6 is concavely provided in a cutting edge-side chip discharge groove formation surface 4 constituting the chip discharge groove 2 of the tool body 1, from a cutting edge 5 and along the cutting edge 5.

According to one implementation, an end mill for orbital drilling includes: a shank; a first cutting edge formed in a peripheral portion of the shank; and a second cutting edge formed in a bottom portion of the shank. At least a chamfered edge is formed on a first ridgeline between a first rake face and a first flank of the first cutting edge.

An object of this disclosure is to provide a cutting insert that is shaped so that a major cutting edge is not damaged easily. In the cutting insert, a major cutting edge, a corner edge, a flat cutting edge and an inner cutting edge are formed on at least an upper surface, a protruding portion protruding outward is formed in a major cutting edge side surface portion of a side surface that corresponds to the major cutting edge, and a first section is formed in which, when viewed from above, the protrusion amount becomes smaller as the protruding portion separates from the corner edge. Furthermore, the cutting insert includes a first clearance angle changing portion in which a clearance angle becomes smaller as a major cutting edge flank portion formed in a major cutting edge side surface portion separates from the corner edge, and a second clearance angle changing portion in which the clearance angle becomes larger as the major cutting edge flank portion separates from the corner edge, wherein the first clearance angle changing portion is preferably positioned closer to the corner edge than the second clearance angle changing portion is, and, of end portions of the first clearance angle changing portion, the value of the clearance angle at a distal end portion from the corner edge is preferably negative.

The technical problem to be solved by the present disclosure is to provide a single-sided high feed cutting insert which can have increased edge strength and reduced cutting load so as to be suitable for high feed machining. To this end, the single-sided high feed cutting insert of the present disclosure comprises: a short cutting edge disposed between a major surface and a short lateral surface; a long cutting edge disposed between the major surface and a long lateral surface; and a corner cutting edge disposed between the short cutting edge and the long cutting edge, wherein the short cutting edge has an outwardly convex curved shape when viewed from the major surface, and a minor surface has a straight shape when viewed from the short and long lateral surfaces, respectively.

A single-sided four-way indexable cutting insert includes a positive basic shape, a rake surface, a peripheral surface including four side abutment surfaces, a base bearing surface and a screw hole connecting the rake and base bearing surfaces. The insert has an imaginary square frustum which defines a square base containing the cutting insert's base bearing surface, and further defines four isosceles trapezoid side surfaces respectively containing the cutting insert's four side abutment surfaces. A material volume V.sub.F of the cutting insert and a void volume V.sub.S of the insert fulfill the condition V.sub.S/V.sub.F0.25.

A single-sided four-way indexable cutting insert includes a positive basic shape, a rake surface, a peripheral surface including four side abutment surfaces, a base bearing surface and a screw hole connecting the rake and base bearing surfaces. The insert has an imaginary square frustum which defines a square base containing the cutting insert's base bearing surface, and further defines four isosceles trapezoid side surfaces respectively containing the cutting insert's four side abutment surfaces. A material volume V.sub.F of the cutting insert and a void volume V.sub.S of the insert fulfill the condition V.sub.S/V.sub.F0.25.

A shaft portion and a blade portion provided on a side surface of the shaft portion are included, and the blade portion includes cutting blades arranged in a plurality of lines on a side surface of the shaft portion along a peripheral direction, and arranged in a plurality of stages in an extending direction of a shaft center of the shaft portion in each line. Further, the cutting blade has a radial-direction clearance angle, a tip end-side clearance angle, and a base end-side clearance angle.

A milling cutter is composed of a tool body having an approximately cylindrical or disk-like shape and a plurality of edge portions provided on at least an outer peripheral portion of one end of the tool body at predetermined intervals along a circumferential direction. The edge portion has a major cutting edge and a minor cutting edge that perform an operation of cutting a workpiece, the major cutting edge is positioned outside the minor cutting edge in a radial direction, and the minor cutting edge has a cutting edge angle that is an angle with respect to a plane orthogonal to a center axis of the tool body and set so as to be an elevation angle open outward in the radial direction. When surface machining is performed on a workpiece with the milling cutter, a high degree of machined surface accuracy equivalent to that obtained by grinding is obtained.

A ball-end mill includes arcuate cutting edges each extending from a tip end to a peripherally outermost point along a S shape curve when viewed from the front side, spirally-shaped, peripheral cutting edges each smoothly connected to each arcuate cutting edge, and a convex rake face of each arcuate cutting edge protruding forward in a rotation direction. Each arcuate cutting edge has a radial rake angle satisfying <, where is a radial rake angle at a radial angle of 5, is a radial rake angle at a radial angle of 90, and is a radial rake angle at a rotationally most projecting point of the arcuate cutting edge. The radial rake angle has the maximum value at a radial angle in a range of 12-40 and continuously decreases in a range from the rotationally most projecting point to the peripherally outermost point.