Abstract: A cutting insert 10 comprises a peripheral side surface 16 comprising a plurality of peripheral side surface parts 16A-16H formed so as to be in rotational symmetry with respect to a central axis AX. In the cutting insert 10, a second end surface 14 is provided with a plurality of inclined surface parts 13A-13H formed so as to be in rotational symmetry with respect to the central axis AX and to be recessed from a peripheral edge part 14A.

Abstract: A cutting insert 10 comprises a peripheral side surface 16 comprising a plurality of peripheral side surface parts 16A-16H formed so as to be in rotational symmetry with respect to a central axis AX. In the cutting insert 10, a second end surface 14 is provided with a plurality of inclined surface parts 13A-13H formed so as to be in rotational symmetry with respect to the central axis AX and to be recessed from a peripheral edge part 14A.

Abstract: A cutting insert has opposing first and second end surfaces, and a peripheral side surface (connecting the end surfaces. A central axis penetrates the two end surfaces. The peripheral sure surface includes an outwardly inclined first side surface part related to a major cutting edge and a second side surface part related to a minor cutting edge. The outwardly inclined first side surface part gradually extends outward from the cutting insert, heading from the first end surface to the second end surface. When a second virtual plane, which is substantially perpendicular to the central axis and passes through the major cutting edge, is defined, an inwardly inclined part, on a back side of the cutting edge, of the second end surface is inclined so as to become more distant from the second virtual plane, heading from the outwardly inclined first side surface part to the central axis.

Abstract: A cutting insert has a first (top) end surface, a second (bottom) end surface, a peripheral side surface connecting the top and bottom end surfaces, and a mounting hole having a central axis O which penetrates the top and bottom end surfaces. Cutting edges are formed on an intersecting edge between the first end surface and the peripheral side surface. The second end surface has an inclined part. When a virtual plane substantially perpendicular to the axis O and passing through any point of the cutting edges is defined, the inclined part is inclined so as to be more distant from the virtual plane, heading from the peripheral side surface to the axis O. A projected part projected in a direction along the axis O is formed in an area around the mounting hole in the inclined part. This reinforces the strength of the mounting hole.

Abstract: In a body for a cutting tool having an insert seat, to which a cutting insert is removably attached, not only a structure for preventing a crack at the insert seat, caused by stress concentration, is adopted, but also the cutting insert is stably seated at and firmly attached to the insert seat. A recessed curve portion is formed at a crossing portion between a bottom surface and a wall surface of the insert seat. As viewed in cross section perpendicular to the bottom surface, the cross-sectional shape of the curve portion includes an arc having a radius R of curvature within a range from 0.5-1.2 mm. A height from the bottom surface to a connecting portion between the wall surface and the curve portion is set within a range from 0.1-0.8 mm.

Abstract: A cutting insert has opposing first and second end surfaces, and a peripheral side surface (connecting the end surfaces. A central axis penetrates the two end surfaces. The peripheral sure surface includes an outwardly inclined first side surface part related to a major cutting edge and a second side surface part related to a minor cutting edge. The outwardly inclined first side surface part gradually extends outward from the cutting insert, heading from the first end surface to the second end surface. When a second virtual plane, which is substantially perpendicular to the central axis and passes through the major cutting edge, is defined, an inwardly inclined part, on a back side of the cutting edge, of the second end surface is inclined so as to become more distant from the second virtual plane, heading from the outwardly inclined first side surface part to the central axis.

Abstract: A cutting insert has a first (top) end surface, a second (bottom) end surface, a peripheral side surface connecting the top and bottom end surfaces, and a mounting hole having a central axis O which penetrates the top and bottom end surfaces. Cutting edges are formed on an intersecting edge between the first end surface and the peripheral side surface. The second end surface has an inclined part. When a virtual plane substantially perpendicular to the axis O and passing through any point of the cutting edges is defined, the inclined part is inclined so as to be more distant from the virtual plane, heading from the peripheral side surface to the axis O. A projected part projected in a direction along the axis O is formed in an area around the mounting hole in the inclined part. This reinforces the strength of the mounting hole.

Abstract: In a body for a cutting tool having an insert seat, to which a cutting insert is removably attached, not only a structure for preventing a crack at the insert seat, caused by stress concentration, is adopted, but also the cutting insert is stably seated at and firmly attached to the insert seat. A recessed curve portion is formed at a crossing portion between a bottom surface and a wall surface of the insert seat. As viewed in cross section perpendicular to the bottom surface, the cross-sectional shape of the curve portion includes an arc having a radius R of curvature within a range from 0.5-1.2 mm. A height from the bottom surface to a connecting portion between the wall surface and the curve portion is set within a range from 0.1-0.8 mm.