Patent ID: 8353646

Claim:
A tool for machining borehole surfaces comprising a base body; a cutting device having at least one cutting die with at least one geometrically defined tool edge, the at least one cutting die being tangentially fastened to an end face of the tool; and at least one guide surface for guiding the tool inside the machined borehole, wherein the at least one cutting die is provided with a rounded cut for producing a support surface adjacent to the tool edge, the support surface being arched with a radius that is smaller than the radius of the borehole to be machined, and the region of the support surface directly adjoining the tool edge resting against the borehole wall to be machined, and the end region of the support surface—viewed in the peripheral direction of the tool—which is situated at a distance from the tool edge being situated at a distance from the wall of the borehole; wherein the support surface has an end region which merges into a free surface via a bend, the free surface having a steeper slope than the end region of the support surface, and a distance between the end region of the support surface from the wall of the borehole is approximately 0.02 mm to approximately 0.001 mm.