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 virtual plane obtained by a locus when a tangent line, which passes through a tool distal end edge, of a virtual circle formed when a tool distal end edge of a cutting edge is rotated in a tool circumferential direction is moved parallel to a tool axial line is a reference plane, an angle (ARt) at which a cross line of the reference plane and the cutting edge virtual plane, is inclined with respect to the tool axial line projected onto the reference plane, is in a range of 30 degrees to 60 degrees, an angle (RR) at which a cutting edge tangent line which passes through the tool distal end edge and extends outward in a tool radial direction, is inclined with respect to a predetermined tool radial direction, which passes through the tool distal end edge, is in a range of 30 degrees to 75 degrees.

A virtual plane obtained by a locus when a tangent line, which passes through a tool distal end edge, of a virtual circle formed when a tool distal end edge of a cutting edge is rotated in a tool circumferential direction is moved parallel to a tool axial line is a reference plane, an angle (ARt) at which a cross line of the reference plane and the cutting edge virtual plane, is inclined with respect to the tool axial line projected onto the reference plane, is in a range of 30 degrees to 60 degrees, an angle (RR) at which a cutting edge tangent line which passes through the tool distal end edge and extends outward in a tool radial direction, is inclined with respect to a predetermined tool radial direction, which passes through the tool distal end edge, is in a range of 30 degrees to 75 degrees.

This disclosure relates to a metal-cutting machine tool with a base body, which is rotatable about an axis of rotation relative to a workpiece to be machined, at least one plate seat disposed outside the axis of rotation on the base body and a cutting insert, which is inserted into the plate seat and held therein by at least one fastening means and which is provided with a coating, at least in the area of its cutting edge. In order to compensate for positional tolerances, according to this disclosure the plate seat comprises a positioning surface oriented toward the axis of rotation, and the cutting insert has a reference surface lying against the positioning surface and facing away from the axis of rotation, for radially determining the position of its cutting edge, wherein the coating is also applied to the reference surface.

This disclosure relates to a metal-cutting machine tool with a base body, which is rotatable about an axis of rotation relative to a workpiece to be machined, at least one plate seat disposed outside the axis of rotation on the base body and a cutting insert, which is inserted into the plate seat and held therein by at least one fastening means and which is provided with a coating, at least in the area of its cutting edge. In order to compensate for positional tolerances, according to this disclosure the plate seat comprises a positioning surface oriented toward the axis of rotation, and the cutting insert has a reference surface lying against the positioning surface and facing away from the axis of rotation, for radially determining the position of its cutting edge, wherein the coating is also applied to the reference surface.

The present invention relates to a tool body provided with at least one insert seat. The insert seat includes a bottom wall surface and a side wall surface. The side wall surface includes a first side wall surface and a second side wall surface. The first side wall surface includes at least two surface portions. The first surface portion is a curved surface having a recessed shape recessed toward a base end of the tool body, and the second surface portion is a curved surface having a recessed shape recessed toward the base end of the tool body, with a greater curvature radius than that of the first surface portion, or a flat surface. The two surface portions both come into contact with a cutting insert.

A cutting tool assembly includes a tool body and a tool holder including a longitudinal axis around which the tool holder is configured to spin. The tool holder includes a central portion connected to the tool body comprising a fastener hole perpendicular with the longitudinal axis and configured to receive a securing fastener, wherein the fastener hole is offset from the longitudinal axis. The tool holder further includes an eccentric drive member connected to the cylindrical portion. The tool holder can optionally further include an end alignment cylinder connected to the eccentric drive member.

A milling tool is disclosed. The milling tool may include an elongated body having a longitudinal axis and a plurality of cutting inserts. The cutting inserts may each have a cutting edge and a cutting radius and be coupled to the body and spaced along the longitudinal axis. One or more of the plurality of cutting inserts may be adjustable (e.g., mechanically adjustable) between first and second cutting radii. A difference between the first and second cutting radii may be at least 10 m. The milling tool may include cutting inserts having a plurality of different cutting radii. The milling tool may be configured to have a length that spans an entire height of an engine bore. The cutting inserts having different radii may compensate for dimensional errors in an engine bore diameter that occur when milling a deep pocket.

A milling tool is disclosed. The milling tool may include an elongated body having a longitudinal axis and a plurality of cutting inserts. The cutting inserts may each have a cutting edge and a cutting radius and be coupled to the body and spaced along the longitudinal axis. One or more of the plurality of cutting inserts may be adjustable (e.g., mechanically adjustable) between first and second cutting radii. A difference between the first and second cutting radii may be at least 10 m. The milling tool may include cutting inserts having a plurality of different cutting radii. The milling tool may be configured to have a length that spans an entire height of an engine bore. The cutting inserts having different radii may compensate for dimensional errors in an engine bore diameter that occur when milling a deep pocket.

An insert attachment mechanism (100) detachably attaches a cutting insert (2) to an insert attachment part (21) of a tool body (3). The insert attachment mechanism includes an adjustment member (30) and a wedge member (10). The adjustment member (30) is arranged on an inner side of the cutting inset so as to act on the cutting insert in the insert attachment part. The adjustment member is advanceable and retractable in a direction of the central axis of a screw member (40) by rotating the screw member. The wedge member and the cutting insert are arranged on the outer side of the adjustment member in the insert attachment part and exert a pressing force against the cutting insert and an inner wall surface of the insert attachment part. The wedge member (10) is configured such that the screw member (40) is accessible from the outer side of the wedge member.