Abstract: An interchangeable tool part for a reamer includes a hard metal cutting plate. The cutting surface of the cutting plate is arranged at a distance of at least 0.02 mm from the cutting edge on one side in the region of the cut part and at least partially has a peak-to-valley height which increases by at least 0.01 mm in order to assure the production of cut fragments in the main cutting area and to prevent a build up of cuts in the region of auxiliary cutting section and/or to simplify the removal of cuts. Also high targets can be reached by virtue of the fact that the cutting plates define at least one cutting cavity in the cutting surface thereof at a distance of at least 0.02 mm from the main cutting edge on the end side in the region of the entry angle.

Abstract: A tool having a base body which carries cutters for machining bores in a workpiece, the cutters being arranged coaxially with one another. The base body further has at least one lifting element, with which the base body can be moved from an eccentric position in relation to an axis of the workpiece bores into a central position, in which the axis of the tool coincides with the axis of the workpiece bores.