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.

A rotary tool may include a holder and a cutting insert. The cutting insert may include an upper surface including a first upper side, a lower surface including a first lower side, and a lateral surface. The lateral surface may include a first lateral surface, a second lateral surface, and a third lateral surface. The first upper side may include a first end. The first end may be located closer to the third lateral surface than the second lateral surface. The first lower side may include a second end. The second end may be located closer to the second lateral surface than the third lateral surface. In a front view of the upper surface, the first lateral surface may include a tip region surrounded by the first end and the second end, and the tip region may be recessed toward the rear end.

An example milling bit comprises a shank and a working sector comprising a cutting anterior part, which is a portion of a hollow sphere, a cutting posterior part fixed to the shank and located between the shank and the spherical anterior part, at least one cutting tooth extending along an entire length of the working sector with a cutting edge, and at least one flute to the cutting tooth extending along length of the working sector following the path of the cutting edge. The spherical anterior part of the working sector is hollow and at least one cutting tooth in the anterior cavity region has a shape of a spherical shell element.

The present disclosure provides a cutting tool that comprises: an end cutting edge that is formed so as to extend radially from the central axis side; a peripheral edge that forms a pair of cutting edges with the end cutting edge; and a chip discharge groove provided around the central axis. The chip discharge groove is formed by two or more grooves that include at least a major groove and a minor groove and have different helix angles from each other. The major groove that forms the peripheral edge on an edge between a peripheral side surface of the cutting tool and such major groove has a helix angle that is the smallest helix angle, and the minor groove that is in contact with the major groove and arranged with its phase shifted forward with respect to the major groove in a tool rotating direction has a helix angle that is greater than the helix angle of the major groove.

An example milling bit comprises a shank and a working sector comprising a cutting anterior part, which is a portion of a hollow sphere, a cutting posterior part fixed to the shank and located between the shank and the spherical anterior part, at least one cutting tooth extending along an entire length of the working sector with a cutting edge, and at least one flute to the cutting tooth extending along length of the working sector following the path of the cutting edge. The spherical anterior part of the working sector is hollow and at least one cutting tooth in the anterior cavity region has a shape of a spherical shell element.