This disclosure relates to a machine tool comprising a tool holder which rotates relative to a workpiece to be machined and has a tool axis, and a plurality of cutting inserts that are removably attached to the tool holder, the active cutting edges of said cutting inserts having a common cutting circle which is coaxial to the tool axis. According to this disclosure, the tool holder has a cylinder-type insert seat shell for radially positioning the cutting inserts, which rotates about the tool axis. The cutting inserts have at least one contact surface that can be brought into contact with the insert seat shell.

A machine reaming tool includes a shank and an interchangeable head assembled on the shank. The interchangeable head on a side that faces the shank includes at least one head groove and at least one head ridge. The shank on a side that faces the interchangeable head includes at least one shank groove and at least one shank ridge. In the assembled condition, the at least one head groove engages into the at least one shank ridge and the at least one shank groove engages into the at least one head ridge.

In order to achieve as highly accurate an alignment of the frictional tool as possible and therefore as high a drilled hole quality as possible during the precision machining of a drilled hole, the cutting edges of the frictional tool are divided into two cutting groups, the cutting edges of which are spaced apart with respect to one another in each case by an axial spacing from one another. Here, the axial spacing is selected in such a way that, at a predefined first, slower feed speed, merely the cutting edges of the first cutting edge group are in engagement with the workpiece and, at a higher, predefined second feed speed, all cutting edges are in engagement with the workpiece.

In order to achieve as highly accurate an alignment of the frictional tool as possible and therefore as high a drilled hole quality as possible during the precision machining of a drilled hole, the cutting edges of the frictional tool are divided into two cutting groups, the cutting edges of which are spaced apart with respect to one another in each case by an axial spacing from one another. Here, the axial spacing is selected in such a way that, at a predefined first, slower feed speed, merely the cutting edges of the first cutting edge group are in engagement with the workpiece and, at a higher, predefined second feed speed, all cutting edges are in engagement with the workpiece.

The invention relates to a reamer (3), having a main body (5) and at least one cutting tip (1) arranged on the main body (5), the cutting tip (1) having a reamer section (7), the cutting tip (1) having, at a distance (A) from the reamer section (7), a roughening section (9) having at least one roughening blade (11), the at least one roughening blade (11) protruding beyond the reamer section (7) by a particular projection (D).

A reamer includes a shank portion extending from a rear end and a cutting portion extending from the shank portion to a front end. The cutting portion includes a plurality of cutting teeth separated by gashes. Each cutting tooth having a cutting edge extending in a longitudinal direction from the front end to proximate the shank portion. The cutting portion includes a margin trailing each cutting edge and extends along each cutting edge to proximate the shank portion. Each cutting tooth also has a primary relief formed between the cutting edge and the front end and a secondary relief extending longitudinally between the margin of one cutting tooth to the cutting edge of an adjacent cutting tooth. A width, W, of each cutting tooth increases in a radially outward direction with respect to the central, longitudinal axis when viewed from the front end of the reamer.