A cutting tool has a holder and an indexable cutting insert secured therein. The holder has a head and a shank extending therefrom along a holder axis, the head having spaced apart lower and upper clamping portions located on opposite sides of a first plane containing the holder axis. The lower clamping portion has spaced apart first and second lower clamping surfaces located on opposite sides of a second plane perpendicular to the first plane, and the upper clamping portion has an upper clamping surface intersected by the second plane. The cutting insert has a peripheral surface with a plurality of circumferentially spaced cutting portions, and the second plane intersects the plurality of cutting portions. The upper clamping surface makes contact with a first abutment portion of the peripheral surface, and a second abutment portion of the peripheral surface makes contact with the first and second lower clamping surfaces.

A cutting insert has a cutting portion corner formed at the intersection of a rake surface, a forward cutting portion surface and a relief surface. A cutting edge is formed at an intersection of the rake surface and the relief surface with a land that is located on the rake surface and that extends along, and negatively away from, the cutting edge. A chip-control arrangement is located at the rake surface and includes an elongated projection and plurality of spaced apart elongated protuberances that extend from the projection to the cutting edge, so that the land has a plurality of spaced apart bulging land portions. A non-rotary cutting tool has an insert holder having an insert pocket and the cutting insert releasably retained therein.

A cutting part of a cutting insert may include a first surface including a corner, a first side, a first region, a second region and a third region. The first region may be located along the corner and the first side. The second region may be located at a more inner part than the first region. The third region may be located at a more inner part than the second region. A boundary between the corner and the first side may be a first point. A boundary between the first region and the second region may be a second point in a cross section that passes through the first point and is orthogonal to the first side. An imaginary straight line passing through the first point and the second point may be a first imaginary straight line. The first imaginary straight line may intersect with the third region.

A cutting tool including a substrate and a coating film disposed on the substrate, wherein the cutting tool includes: a rake face, a flank face contiguous to the rake face; and a cutting edge region composed of a boundary part between the rake face and the flank face, wherein the coating film includes a TiSiCN layer, the TiSiCN layer has: a first TiSiCN layer positioned in the rake face; and a second TiSiCN layer positioned in the cutting edge region, the first TiSiCN layer has a composition of Ti.sub.(1-Xr)Si.sub.XrCN, the second TiSiCN layer has a composition of Ti.sub.(1-Xe)Si.sub.XeCN, and the Xr and the Xe each represent 0.010 or more and 0.100 or less, and satisfy a relationship of Xr?Xe?0.003.

Indexable, double-sided turning inserts for turning operations and and a turning tool are provided with cutting edges at alternating corners on opposite sides of the insert. Chipbreaker structures can be provided without interfering with providing large supporting surfaces. When the insert is used in a cutting operation, chips from one of the cutting edges in use are unlikely to damage cutting edges that are not in use but are on adjacent corners.

A cutting tool according to an aspect of the present invention is a cutting tool for cutting a rotationally symmetrical surface of a rotating workpiece. The cutting includes the step of feeding the cutting tool in a direction inclined with respect to a rotational axis of the rotationally symmetrical surface, while holding the cutting tool in contact with the rotationally symmetrical surface. In the step of feeding the cutting tool, the cutting tool has a point that is in contact with the rotationally symmetrical surface and the point shifts as the cutting tool is fed. The cutting tool includes: a rake face; a flank face; and a cutting edge connecting the rake face and the flank face. The cutting edge as seen from above the flank face has a shape including at least one arc, and the arc has a radius of curvature of not less than 100 mm and not more than 500 mm.

A cutting insert includes an upper surface and upper edge. The upper surface includes a second side part, a first corner part, and a second corner part. The upper surface further includes a first surface and a second surface. The upper edge includes a first edge located at the first corner part, a second edge located at the second side part, and a third edge located at the second corner part. The second surface includes a first region extending toward the first corner part, and a second region extending toward the second corner part. A distance between the first region and the upper edge is smaller at a side of the second edge than at a side of the first edge. A distance between the second region and the upper edge is smaller at a side of the second edge than at a side of the third edge.

A double-sided cutting insert with orientation-assisting geometry includes identical and opposite first and second main surfaces and a peripheral surface which extends therebetween. The insert further includes a median plane located midway between the first and second main surfaces and opposite first and second clamping recesses opening out respectively to the first and second main surfaces. Projections onto the median plane of at least portions of the first and second clamping recesses are rotationally offset from one another about a central axis.

A cutting insert includes opposing insert first and second side surfaces. The insert first side surface includes a first mounting arrangement. The first mounting arrangement includes a) at least one first side abutment surface facing away from the insert second side surface, b) a first stopper abutment surface oriented transversely to the at least one first side abutment surface and c) two opposite-facing first wedge abutment surfaces oriented transversely to the at least one first side abutment surface and converging forwardly. An insert holder has a corresponding pocket mounting arrangement for engagement with the first mounting arrangement.

A cutting tool is rotatable about a central axis and has a front end in an axial direction along the central axis. The cutting tool includes a body, a blade, a first attachment screw, an adjustment piece, and a second attachment screw. The body has an outer peripheral surface. A pocket is formed in the outer peripheral surface at an end portion on the front end side. The blade is attached to the body by screwing the first attachment screw into the body in the pocket. The blade has a blade side surface facing inward in a radial direction that is orthogonal to the axial direction and that passes through the central axis. An inner wall surface of the pocket has a contact surface facing the blade side surface with a space being interposed between the blade side surface and the contact surface in the radial direction.