A rotary cutting tool is provided which, although it has a simple configuration, allows the arrangement of each cutting edge to be easily adjusted. A first cartridge mounting seat has an upper wall surface opposing an outer side surface of a cartridge and further has a first recessed part into which a protrusion is inserted and which comes into contact, at a bottom thereof, with a leading end of the protrusion. A second cartridge mounting seat has an upper wall surface opposing an outer side surface of a cartridge and further has a second recessed part into which a protrusion is inserted and which comes into contact, at a bottom thereof, with a leading end of the protrusion. A depth of the second recessed part is greater than a depth of the first recessed part. An amount of protrusion P of the protrusion is equal to or greater than the depth of the second recessed part.

A rotary cutting tool is provided which, although it has a simple configuration, allows the arrangement of each cutting edge to be easily adjusted. A first cartridge mounting seat has an upper wall surface opposing an outer side surface of a cartridge and further has a first recessed part into which a protrusion is inserted and which comes into contact, at a bottom thereof, with a leading end of the protrusion. A second cartridge mounting seat has an upper wall surface opposing an outer side surface of a cartridge and further has a second recessed part into which a protrusion is inserted and which comes into contact, at a bottom thereof, with a leading end of the protrusion. A depth of the second recessed part is greater than a depth of the first recessed part. An amount of protrusion P of the protrusion is equal to or greater than the depth of the second recessed part.

In an embodiment, a cutting tool includes a holder that is a columnar body and includes a pocket in which an insert disposed. The pocket includes a first surface in contact with the insert, a second surface, and a projecting portion. The second surface is disposed further forward in a rotational direction of a rotational axis than the first surface, and disposed on a radial inner side of the holder. The projecting portion is disposed closer to a radial outer circumferential side of the holder than the first surface and projects forward in the rotational direction of the rotational axis. The second surface is inclined and comes closer to an outer circumference of the holder as going forward in the rotational direction of the rotational axis, in a front view of a first end.

In an embodiment, a cutting tool includes a holder that is a columnar body and includes a pocket in which an insert disposed. The pocket includes a first surface in contact with the insert, a second surface, and a projecting portion. The second surface is disposed further forward in a rotational direction of a rotational axis than the first surface, and disposed on a radial inner side of the holder. The projecting portion is disposed closer to a radial outer circumferential side of the holder than the first surface and projects forward in the rotational direction of the rotational axis. The second surface is inclined and comes closer to an outer circumference of the holder as going forward in the rotational direction of the rotational axis, in a front view of a first end.

This sectional hob is provided with: a cylindrical hob body; a plate-shaped blade having a saw-toothed cutting edge, the blade being disposed in at least one attachment seat formed in an outer peripheral part of the hob body such that a direction of the cutting edge is parallel to a center axis direction of the hob body; and a plurality of wedge members configured to detachably-fix the blade disposed in the attachment seat to the hob body, the wedge members being installed in a recess formed on the outer peripheral part of the hob body, wherein the recess is adjacent to the attachment seat in a circumferential direction of the hob body, and the plurality of the wedge members are disposed in a line in the center axis direction in the recess.

This sectional hob is provided with: a cylindrical hob body; a plate-shaped blade having a saw-toothed cutting edge, the blade being disposed in at least one attachment seat formed in an outer peripheral part of the hob body such that a direction of the cutting edge is parallel to a center axis direction of the hob body; and a plurality of wedge members configured to detachably-fix the blade disposed in the attachment seat to the hob body, the wedge members being installed in a recess formed on the outer peripheral part of the hob body, wherein the recess is adjacent to the attachment seat in a circumferential direction of the hob body, and the plurality of the wedge members are disposed in a line in the center axis direction in the recess.

The drill has a rake face, a flank face, and an outer circumferential surface. The flank face is continuous to the rake face. The outer circumferential surface is continuous to both the rake face and the flank face. A ridgeline between the rake face and the flank face constitutes a cutting edge. A ridgeline between the rake face and the outer circumferential surface constitutes an outer circumferential end. A groove is provided cyclically in the rake face to extend at an angle relative to an axis of the drill, the angle being larger than a helix angle of the drill. The groove has a depth of more than or equal to 1.5 m.

The drill has a rake face, a flank face, and an outer circumferential surface. The flank face is continuous to the rake face. The outer circumferential surface is continuous to both the rake face and the flank face. A ridgeline between the rake face and the flank face constitutes a cutting edge. A ridgeline between the rake face and the outer circumferential surface constitutes an outer circumferential end. A groove is provided cyclically in the rake face to extend at an angle relative to an axis of the drill, the angle being larger than a helix angle of the drill. The groove has a depth of more than or equal to 1.5 m.

A slitting cutter having a disk-shaped cutter body with a plurality of circumferentially spaced insert receiving portions and a plurality of cutting inserts retained therein. Each insert receiving portion has first and second clamping jaws spaced apart by an insert receiving slot, the first clamping jaw resiliently displaceable and having a resilient axis of rotation. The number of cutting inserts resiliently clamped in the slitting cutter is an inner cutting diameter defined by the plurality of resilient axes of rotation multiplied by a spacing factor of between 0.15 and 0.30. A tool key having first and second key prongs is used in combination with the slitting cutter. The second key prong has a thrust surface with a concave profile. In a partially assembled position of the slitting cutter the thrust surface contacts at least one of two spaced apart first and second corner surfaces of the respective cutting insert.

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.