A method to form a surface on a metal work piece comprising a first machining step of - providing a turning insert comprising a first cutting edge , a second cutting edge and a convex nose cutting edge connecting the first and second cutting edges, - providing a turning tool comprising the turning insert and a tool body , the tool body having a front end and a rear end , a main extension along a longitudinal axis (A2) extending from the front end to the rear end , and an insert seat formed in the front end in which the turning insert is mounted, - selecting a nose angle (α) formed between the first and second cutting edges to be less than or equal to 85°, wherein the method comprises the further steps of - adapting the orientation of the second cutting edge such that it forms a back clearance angle (ψ) of more than 90° in a feed direction , - positioning all parts of the turning insert ahead of the nose cutting edge in the feed direction , - setting the longitudinal axis (A2) of the tool body at an angle greater than zero but less than or equal to 90 ° relative to a rotational axis (A3) of the metal work piece , - rotating the metal work piece around the rotational axis (A3) in a first direction, - moving the turning insert in a direction parallel to or at an angle less than 45° relative to the rotational axis (A3) such that the first cutting edge is active and ahead of the nose cutting edge in the feed direction and such that the surface at least partly is formed by the nose cutting edge , characterised in that , the method further comprises the step of - setting the back clearance angle (ψ) constant in relation to the feed direction during the formation of the surface . - providing a turning insert comprising a first cutting edge , a second cutting edge and a convex nose cutting edge connecting the first and second cutting edges, - providing a turning tool comprising the turning insert and a tool body , the tool body having a front end and a rear end , a main extension along a longitudinal axis (A2) extending from the front end to the rear end , and an insert seat formed in the front end in which the turning insert is mounted, - selecting a nose angle (α) formed between the first and second cutting edges to be less than or equal to 85°, - adapting the orientation of the second cutting edge such that it forms a back clearance angle (ψ) of more than 90° in a feed direction , - positioning all parts of the turning insert ahead of the nose cutting edge in the feed direction , - setting the longitudinal axis (A2) of the tool body at an angle greater than zero but less than or equal to 90 ° relative to a rotational axis (A3) of the metal work piece , - rotating the metal work piece around the rotational axis (A3) in a first direction, - moving the turning insert in a direction parallel to or at an angle less than 45° relative to the rotational axis (A3) such that the first cutting edge is active and ahead of the nose cutting edge in the feed direction and such that the surface at least partly is formed by the nose cutting edge , characterised in that , - setting the back clearance angle (ψ) constant in relation to the feed direction during the formation of the surface . <EOS>