A rotary cutting tool includes a cutter body having a plurality of insert-receiving pockets. Each pocket includes a bottom support surface, an axial support surface, a radial support surface, a top clearance surface and an intermediate clearance surface extending between the axial support surface and the top clearance surface. A cutting insert includes a helical top surface, a helical side surface, a side surface opposite the helical side surface, a pair of opposed side walls, a bottom surface, and a cutting edge formed at an intersection between the helical top surface and the helical side surface. The cutting insert further includes an undercut for accommodating the axial support surface, the top clearance surface and the intermediate clearance surface of the pocket when the cutting insert is mounted in the pocket.

Cutting insert with a cuboid body has a substantially square top face and bottom face, said top face and bottom face connected by four peripheral adjoining side surfaces. At least two cutting edges are formed at the transition of the top face to at least two side surfaces, that cutting edges defining a plane of the top face. To provide a cutting insert and a corresponding tool suited to produce valve seat surfaces with high precision but still having a rather simple construction and being precisely mountable with ease and less efforts of adjustment, the plane defined by the top face cutting edges of the cutting insert has maximum dimensions of 7 mm7 mm, where the bottom face has a supporting surface formed exactly parallel to the plane defined by the top face cutting edges by means of grinding within a tolerance of less than 5 angular minutes.

A cutting insert has first and second end surfaces, a peripheral side surface, a reference central axis A perpendicular to and passing through the two surfaces, and a cutting edge having at least one circular-arc-shaped cutting edge. A contact surface portion is formed in the second end surface. The arc-shaped cutting edge is part of virtual circle having a center E which is spaced apart from the central axis A. A longitudinal plane B includes the central axis A and the center E; a median plane C perpendicular to the central axis A passes midway between the two end surfaces; and a virtual plane D perpendicular to both the longitudinal plane B and the median plane C, intersects the circular-arc-shaped cutting edge and traverses the contact surface portion. In a cross-section along the virtual plane D, the contact surface portion is inclined relative to the median plane C.

A milling tool has single sided and indexable milling inserts having a round basic shape. Each milling insert has a plurality of tangentially spaced-apart and alternately usable cutting edges, which individually fall archedly from a first end, situated closest to an upper reference plane, to a lowest point, from which it again rises toward a second end. A reinforcing chamfer surface included in the cutting edge is formed with an increasing width in a direction from the first end of the cutting edge toward the second end.

A cutting insert according to one embodiment includes upper and lower surfaces, a side surface including a front side surface, a rear side surface, and a pair of horizontal side surfaces, a first cutting edge, a second cutting edge, and a through hole extending from the upper surface to the lower surface. An opening of the through hole on a side of the upper surface is provided closer to a ridge line where the upper surface and the front side surface intersect each other than a ridge line where the upper surface and the rear side surface intersect each other. An opening of the through hole on a side of the lower surface is provided closer to a ridge line where the lower surface and the rear side surface intersect each other than a ridge line where the lower surface and the front side surface intersect each other.

A land preparation tool includes a cutting surface having a blade and a mounting interface opposite the cutting surface. The mounting interface of the land preparation tool is configured to detachably connect to a tool holder having a top surface, an end surface, a mounting surface opposite the end surface, and opposing first and second side surfaces extending between the end surface and the mounting surface. The mounting surface has an apex extending downwardly from the top surface and first and second mounting faces. The first mounting face extends inwardly from the first side surface toward the apex and the second mounting face extends inwardly from the second side surface toward the apex.

A land preparation tool includes a cutting surface having a blade and a mounting interface opposite the cutting surface. The mounting interface of the land preparation tool is configured to detachably connect to a tool holder having a top surface, an end surface, a mounting surface opposite the end surface, and opposing first and second side surfaces extending between the end surface and the mounting surface. The mounting surface has an apex extending downwardly from the top surface and first and second mounting faces. The first mounting face extends inwardly from the first side surface toward the apex and the second mounting face extends inwardly from the second side surface toward the apex.