Abstract: A drill for chip forming metalworking includes three cutting edge structures spaced circumferentially apart. Each cutting edge structure includes a radially outer cutting edge and a radially inner cutting edge. Each radially inner cutting edge is inclined in a radially inner and axially rearward direction from a radially inner end of its associated radially outer cutting edge. That radially inner end constitutes a breakpoint between each radially outer cutting edge and its respective radially inner cutting edge. The breakpoints lie in a common circle whose center coincides with the center axis of the drill.

Abstract: The invention relates to a drilling tool comprising a tool holder, on whose front face interchangeable cutting attachments are fixed and which has a shaft part on the opposite end to said attachments and an adjusting device for minimizing the tolerance measurement determined by the drilling system. In order to improve the aforementioned adjusting device, the invention is characterized in that the tool holder (1) has groove-shaped recesses (5, 8), which lie on respective diametrically opposed sides and which are eccentrically arranged on a plane that is perpendicular to the longitudinal axis of the tool holder. Said groove-shaped recesses have a half-cylinder extension on each of the sides facing the longitudinal axis of the tool holder. A bolt (2, 3), whose dimensions correspond to the size of the cylinder, is located in each extension. The first bolt (2) is connected to a tapered adjusting element (9) using a double-threaded screw (11) which is positioned radially in relation to the tool holder (1).