Turning tool

An indexable cutting insert for a turning tool for material processing machines with a first axis of symmetry, wherein at least a first group of main cutting edges are arranged n-fold rotationally symmetrically with respect to the first axis of symmetry, with n being greater than or equal to 2,

• wherein these main cutting edges converge with respective adjacent first secondary cutting edges in a respective cutting corner of a first group of cutting corners at a corner angle of at most 90 degrees, and having at least one fastening bore passing through the indexable cutting insert parallel or coaxially to the first axis of symmetry,
• wherein these main cutting edges each merge directly into a respective adjoining side edge, which side edges extend parallel to a plane oriented orthogonally to the first axis of symmetry and extend over a corner with an obtuse angle or an arcuate connecting piece to the adjoining secondary cutting edge,
• wherein the indexable cutting insert is constructed rotationally symmetrically by 180 degrees about a second axis of symmetry lying in its central plane and orthogonal to the first axis of symmetry, and in so doing has a second group of main cutting edges, secondary cutting edges and cutting corners, which is rotationally symmetrically opposite the first group of main cutting edges, secondary cutting edges and cutting corners about the second axis of symmetry, and
• wherein at least the main cutting edges, starting directly from the associated cutting corners and extending to the respective adjoining side edges, form a single cutting edge of constant slope having a continuous acute cutting edge angle between 0.1 and 70 degrees relative to the plane oriented orthogonally to the first axis of symmetry.