This invention relates to finish machining, including a tool and the method of its use. Embodiments of this invention allow a cutting insert to be indexed quickly without loosening the insert retainer (screw or clamp) and not changing the depth-of-cut position of the tooth tip. The indexing motion is achieved by rotating a rotor, either manually or by way of a motor included on the tool. In some cases, between indexes, a small angle may be imparted to the rotor in order to adjust slightly the depth-of-cut position of the tooth tip in order to compensate for it being worn, or in other cases to precisely match the depth of cut of the tooth tips on multiple cutting teeth. The method involves setting up the path the tool will follow, then setting the feed per finishing tooth to be unconventionally large relative to the maximum depth of cut along the path. Using a round cutting insert, in particular a tangentially-mounted one or one that exhibits comparable curved edge profile, provides a large tooth-tip radius of curvature which in turn results in a good/smooth surface finish in spite of the unconventionally high feed per finishing tooth.

Provided is a cutting tool for back turning capable of improving chipping resistance. A cutting tool wherein a wall surface of a chip breaker includes a first wall surface that is formed along a first ridgeline, and a reinforcing surface that is connected to the first wall surface and a first end surface at an end portion of the chip breaker on the side of a first cutting edge, and that forms an angle of 90 degrees or an obtuse angle with the first end surface.

A cutting insert for a tool for machining a workpiece, comprising a first side, an opposite second side and a bore running along a bore axis. The bore penetrates the cutting insert and extends from the first side to the second side. The cutting insert comprises at least three cutting heads arranged distributed on a periphery of the cutting insert, wherein each of the at least three cutting heads comprises a cutting edge, which runs transversely to the first side and the second side and extends between the first side and the second side. The at least three cutting heads comprise a first cutting head, a second cutting head, which in a peripheral direction directly follows the first cutting head, and a third cutting head, which in the peripheral direction directly follows the second cutting head. The cutting insert has a first support surface arranged on the first side, which first support surface runs orthogonal to the bore axis and at least partially surrounds the bore. The cutting insert is rotationally symmetric to the bore axis and mirror-symmetric to a center plane which runs perpendicular to the bore axis and divides the cutting insert into two equally sized halves. Viewed in a top view along the bore axis, an imaginary straight connecting line between the cutting edge of the first cutting head and the cutting edge of the third cutting head intersects neither the bore nor the first support surface.

A cutting insert has cutting edges having the same shape and provided at respective corners of a polygon in rotational symmetry about the center axis of the polygon, is clamped in an upright position to a holder, and has a negative side rake angle on a rake face of a side cutting edge. A side cutting edge is present at an intersection ridge between a polygonal face and an outer peripheral face. The outer peripheral face includes a rake face of the cutting edge and a flank of an end cutting edge of another cutting edge different from the side cutting edge. The flank has a positive slope angle in opposition to a negative side rake angle of the side cutting edge. A breaker groove extending in a front-rear direction is formed in the rake face and cuts into the flank, in such a manner as to divide the rake face.

The invention relates to a cutting insert holder, having a central axis and at least one first receptacle for fastening a first cutting insert to the cutting insert holder, and having at least one second receptacle for fastening at least one second cutting insert to the cutting insert holder, wherein the first receptacle and the second receptacle are arranged offset from each other in the circumferential direction about the central axis, wherein the first receptacle and the second receptacle are configured and arranged in such a way that a first rake face associated with an active main cutting edge of a first cutting insert arranged in the first receptacle has a first orientation along the circumferential direction, wherein a second rake face associated with an active main cutting edge of a second cutting insert arranged in the second receptacle has a second orientation along the circumferential direction).

A cutting insert for a tool for machining a workpiece, comprising a first cutting edge and a first cutting insert bore, wherein the cutting insert has an elongate shape and extends along a cutting insert longitudinal direction, wherein the first cutting insert bore extends along a first bore axis, which runs substantially orthogonally to the cutting insert longitudinal direction, wherein the cutting insert has a laterally protruding elevation, which is arranged on a side of the cutting insert that is oriented transversely to the first bore axis, and wherein on the elevation are arranged a first lateral holder contact surface, an axial holder contact surface and a first horizontal holder contact surface for the bearing contact of the cutting insert against a tool holder, wherein the first lateral holder contact surface runs substantially orthogonally to the first bore axis, and wherein the axial holder contact surface and the first horizontal holder contact surface run substantially orthogonally to the first lateral holder contact surface and transversely to each other.

A cutting insert according to an aspect includes a base portion and a cutting portion. The cutting portion includes an upper surface, a side surface, a ridge line including a first ridge line and a second ridge line, and an intersection point. The upper surface includes a top surface region and a rising surface region located between the top surface and the ridge line, and having a shape protruding toward the intersection point. In a top view, a first distance from the first ridge line to the rising surface increases as close to the intersection point, and a second distance from the second ridge line to the rising surface increases as close to the intersection point.

Provided is a cutting insert that improves chip control performance. In a cutting insert for back turning process, a chip breaker wall face, of a chip breaker, facing the axial feed direction includes: when viewed from a first face side, a first wall face portion configured so that a ridgeline connecting a top portion of the chip breaker and the first wall face portion is a straight line; and a second wall face portion connected to the first wall face portion on a first cutting edge side and configured so that a ridgeline connecting the top portion of the chip breaker and the second wall face portion is closer to a second cutting edge side than the straight line.

Provided is a cutting tool in which one end side of a protruding cutting edge is sharpened while wear resistance is improved. The cutting tool of the present invention includes an end surface, a peripheral side surface that intersects the end surface, and a cutting edge in an intersecting ridgeline portion between the end surface and the peripheral side surface. When first and second points (A and B) are set on the cutting edge, the first point (A) protrudes further toward an outer side of the cutting tool than the second point (B). The cutting tool has a coating film on its surface. The cutting edge has a portion in which the thickness of the coating film gradually increases toward the second point (B) from the first point (A).

The invention relates to a cutting tool with a holder, a cutting insert and a screw, wherein the holder has at least one seat with a base, a first side wall and a second side wall, wherein in a plane parallel to the base the first side wall extends in a first direction and the second side wall includes an acute angle (C) with the first side wall, wherein the base has a threaded hole for receiving the screw, wherein the cutting insert has a cut-out for the screw, wherein the cutting insert has a base contact surface, a first positioning surface and a second positioning surface, and wherein in a locked position the base contact surface, the first positioning surface and the second positioning surface of the cutting insert contact the base, the first side wall and the second side wall of the at least one seat, respectively, wherein the second side wall is offset from the threaded hole in the first direction towards a front end of the seat, and in that a screw head of the screw and the cut-out of the cutting insert are provided with complementary conical surfaces, such that when tightening the screw the cutting insert is forced with the first positioning surface and the second positioning surface against the first side wall and the second side wall, respectively.