A holder for a cutting tool for processing of workpieces has a first part for holding a cutting tool (150), a second part (120) to which the first part is fastened, and a fastening element (140). An adjustment element adjusts the position of the first part in relation to the second part. The first and second parts have a first bore and a second bore for receiving the fastening element and a recess (118, 128) for receiving the adjustment element. The first part has an abutment surface (115) placed onto a contact surface (122) of the second part, such that the central axes (A-A) for the first and second bores become parallel. The abutment surface of the first part and the contact surface of the second part are inclined in relation to the feeding axis (G-G) of the work piece towards the cutting tool (150).

According to the present disclosure, a cutting insert includes an upper surface having a polygonal shape and includes a corner, a side surface adjacent to the upper surface, a cutting edge and a protrusion. The cutting edge is located at a ridge part in which the upper surface intersects with the side surface and includes a corner part located at the corner. The protrusion is located on the upper surface. The protrusion includes a first protrusion on a bisector of the corner in a top view. The protrusion further includes a second protrusion adjacent to the first protrusion in a direction orthogonal to the bisector. The second protrusion is closer to the corner than the first protrusion in the top view.

The invention relates to a groove cutting tool having: a body and a holder wherein the holder is slidably mounted in the body. The holder has a first end at which a blade is mounted and a second end, distal in a slidable direction of the holder, from the first end. A drive pinion, located towards the second end, is configured to be in rotational communication with the blade.

Tool for machining a workpiece, comprising: a cutting insert; and a cutting insert holder comprising a first cutting insert receptacle extending along a first center axis and a second cutting insert receptacle extending along a second center axis, into which the cutting insert is selectively receivable; wherein the first and second center axes intersect at an imaginary crossing point located in a region that is covered by the cutting insert when the cutting insert is received in the first cutting insert receptacle as well as when the cutting insert is received in the second cutting insert receptacle.

According to the present disclosure, a cutting insert includes an upper surface having a polygonal shape and includes a corner, a side surface adjacent to the upper surface, a cutting edge and a protrusion. The cutting edge is located at a ridge part in which the upper surface intersects with the side surface and includes a corner part located at the corner. The protrusion is located on the upper surface. The protrusion includes a first protrusion on a bisector of the corner in a top view. The protrusion further includes a second protrusion adjacent to the first protrusion in a direction orthogonal to the bisector. The second protrusion is closer to the corner than the first protrusion in the top view.