Cutting tool for machining a workpiece

A cutting insert for a cutting tool having a holder with a first interface that is arranged at a front end of the holder, comprising:

• a second interface,
• wherein the second interface is arranged at a rear side of the cutting insert and corresponds to the first interface of the holder,
• wherein the second interface is configured to couple the cutting insert to the holder;
• a third interface,
• wherein the third interface is arranged at a top face of the cutting insert opposite the rear side of the cutting insert,
• wherein the third interface is configured to couple the cutting insert to a corresponding fourth interface;
• a central through bore that extends along a longitudinal axis of the cutting insert;
• and
• at least one cutting element arranged on a periphery of the cutting insert,
• wherein the second interface corresponds to a first type of interface and the third interface is a second type of interface that is different from the first type of interface,
• wherein the second type of interface does not correspond to the first type of interface, and
• wherein the third interface comprises:
• at least one radial contact surface, which runs parallel to the central through bore, and
• a substantially flat axial contact surface, which is arranged perpendicular to the longitudinal axis.

A spacer element for a cutting tool having a holder, a first and a second cutting insert, wherein the holder has a first interface that is arranged at a front end of the holder, wherein the first cutting insert has a second interface, which is arranged at a rear side of the first cutting insert and corresponds to the first interface of the holder, and a third interface that is arranged at a top face of the first cutting insert opposite the rear side of the first cutting insert, and wherein the second cutting insert has a sixth interface, which is arranged at a rear side of the second cutting insert, the spacer element comprising:

• a fourth interface,
• wherein the fourth interface is arranged at a rear side of the spacer element and corresponds to the third interface,
• wherein the fourth interface is configured to couple the spacer element to the first cutting insert;
• a fifth interface,
• wherein the fifth interface is arranged at a top face of the spacer element opposite the rear side of the spacer element,
• wherein the fifth interface is configured to couple the spacer element to the second cutting insert;
• and
• a central through bore that extends along a longitudinal axis of the spacer element;
• wherein the fifth interface is a first type of interface and the fourth interface corresponds to a second type of interface that is different from the first type of interface,
• wherein the second type of interface does not correspond to the first type of interface,
• wherein the fourth interface comprises:
• at least one radial contact surface, which runs parallel to the longitudinal axis, and
• a substantially flat axial contact surface, which fixes the spacer element in axial direction such that the spacer element can be shortened at its rear side, such that the fourth interface continues to correspond to the third interface.