A rotary cutting tool. The tool has a body with outside diameter (OD), and outer surface, and a longitudinal axis, a plurality of flutes, helical in some embodiments. Flutes include a narrow leading edge land portion with circular segment profile and having flute cutting edge portions along a substantially uniform circumferential location, with an eccentric relief margin rotationally rearward of the narrow leading edge land portions. Face portions are provided with face cutting edge portions, and with a first dish portion adjacent each of the cutting edge portions sloping inwardly and downwardly generally toward a central longitudinal axis at a first dish angle alpha () Corner blend portions extend from flute cutting edge portions to the face cutting edge portions. Corner blend portions are provided in a variety of profiles, including an embodiment wherein the profile of the corner blend portions are truncated before the segment of curvature becomes tangential to the face cutting edge portions. Large core diameters of cutting tools are provided, which gives high strength at when working with axial depths of cut of about three times outside tool diameter or less.

The radial run-out tool (2), particularly a drill or a cutter, has a basic body (12) extending in an axial direction (4) and comprises at least two chip grooves (14), to which a guide chamfer (22) is connected in the rotational direction (24), with a ridge (15) being formed between them. A radial clearance is connected to the guide chamfer (22). In order to enable simple and economical production of such type of radial run-out tool (2), an unprocessed rod (30) is ground non-concentrically, in a first process step, such that a radius (R) of the unprocessed rod (30) varies, depending on the angle, between a maximum radius (R2) and a minimum radius (R1). In a second process step, the chip grooves (14) are grounded down such that the guide chamfers (22) are formed at the positions with the maximum radius (R2) and the radius (R) is subsequently reduced downstream of the respective guide chamfer (22) in order to form the radial clearance (28).

An end mill includes end cutting edges located at a front end side of a cutting edge portion of a body including rotation axis, peripheral cutting edges, and helically extending flutes. Each of the peripheral cutting edges and the flutes are alternately located from the front end side to a rear end side, and a first distance between a deepest position of the flute and the rotation axis is equal among the respective flutes in a cross section taken along the rotation axis. The flute includes a first region located at a side of the peripheral cutting edge and includes the deepest position, a second region located at a side of a heel, and a boundary. A second distance from the rotation axis to the boundary located at the rear end side is larger than the second distance located at the front end side.

A reusing method of an end mill 1, in which an end mill (1) has a margin which is a part of a circle having a diameter identical to a diameter of a shank part (3), the margin being provided on an outer edge of a cutting part (2), a base material of the end mill (1) is machined in advance so as to have coaxiality having equal accuracy to coaxiality for the cutting part (2), the shank part (3) is an unmachined part left without cutting the base material, the margin is a part of an outer peripheral surface of the base material left without cutting the base material when the outer edge is formed by cutting the base material, and when the cutting part (2) is worn out, the cutting part (2) is cut off and a new cutting part 2 is machined on the shank part (3) while a part of outer peripheral surface of the shank part is left as the margin without cutting, the new cutting part 2 having accuracy of coaxiality and an outer diameter identical to those of the cutting part (2).

A metal cutting milling tool includes a body having a front end, a plurality of land portions extending axially rearwards from the front end, and a plurality of chip rooms extending axially rearwards from the front end. Each land portion is delimited by a leading and a trailing surface. Each land portion includes an insert seat for receiving a cutting insert. Each chip room is positioned between two adjacent land portions and is delimited by a chip room surface having the trailing surface of first land portion, the leading surface of a second land portion and a bottom surface positioned between the trailing and leading surface. Each chip room surface has a curvature with a smallest radius. The smallest radius in a second cross section and the smallest radius in a third cross section are larger than the smallest radius in a first cross section.

An end mill has a shank section and a cutting section connected thereto. The cutting section includes a core supporting at least two spaced apart teeth that have a cutting edge extending in the axial direction with respect to the axis of rotation of the end mill. Each cutting edge has a flute associated therewith and each flute has, for each cross-section of the end mill perpendicular to the axis of rotation thereof, a bottom point on the core at a shortest distance to the axis of rotation. At least two flutes have a shortest distance that varies differently with the distance to a cutting end of the end mill.

An end mill, preferably made of solid carbide, with a fastening section and a cutting area, in which the cutting area is formed by a core and three or four cutting edges running helically around the axis of rotation of the end mill and arranged around core; each of which has a peripheral main cutting edge and a secondary cutting edge on a face of the cutting area. On the face of the cutting area at least one point thinning of core is provided between two adjacent cutting edges. In order to create end mills that are simple to manufacture and optimized for drilling, the point thinning has an angle of 30 to 40 relative to the axis of rotation of the end mill.

An end mill includes a body including an axis, first cutting edges on a side of a front end of the body, second cutting edges at a rear side of the respective first cutting edges, flutes located along the second cutting edges, and heels located along the flutes. A shape of each of the flutes in a cross section includes a first concave curve on a side of the second cutting edges, a second concave curve on a side of the heels, and a protrusion located between the two concave curves, the protrusion includes two concave curves intersect each other, and a ratio of a distance from a circle including a maximum diameter in the body centered on the axis to a top of the protrusion to a distance H from the circle to the second cutting edge is 0.1 to 0.4.

In a formed end mill, a peripheral cutting edge has a smaller-diameter cutting part and a larger-diameter cutting part. An imaginary line obtained by lining up a deepest point of a flute bottom of a chip discharge flute, which appears in a cross-sectional view perpendicular to an axis of an end mill body, in an extending direction of the chip discharge flute is defined as a virtual flute bottom line. A flute helix angle, which is formed between the virtual flute bottom line and the axis, in a side view when the end mill body is seen from a radial direction orthogonal to the axis, is 0 degrees or more at a distal end part of the chip discharge flute in the axial direction, and increases gradually from the distal end part toward a posterior end in the axial direction.

A milling cutter includes a shank and a cutting head attached to the shank. The cutting head has a plurality of helical teeth, each tooth including a cutting tip, a leading face and a rear face. A flute is defined between the leading face of a trailing tooth, and a rear face of an immediately preceding tooth. A gully of the flute has a flute base with a portion that is planar or convex in profile to provide additional volume for effective chip evacuation. A method for manufacturing the milling cutter includes rotating a cylindrical blank about its own longitudinal axis, rotating a disc-shaped flute grinding wheel) about a rotational axis of a flute wheel and moving the grinding wheel in a longitudinal direction so as to form the helical flute with the gully having the flute base with the planar or convex portion in profile.