Tool

1. A cutting insert for turning, comprising an upper surface, a lower surface substantially parallel with the upper surface, and at least three side surfaces extending between the upper and lower surfaces, a transition between two adjacent side surfaces forming a rounded nose radius surface at a cutting insert corner, a peripheral land bridging the upper surface and side surfaces at least at the corner portion at a chamfer angle, and an intersection of the land and the nose radius surface forming a nose cutting edge, the nose cutting edge being defined by at least one radius, the cutting corner comprising at least one curved wiper edge, wherein the chamfer angle in a cross-section at the nose cutting edge is smaller than the chamfer angle in a cross-section a distance away from the nose cutting edge and the chamfer angle has a minimum at a bisector of the corner portion.

2. The cutting insert according to claim 1 , wherein the chamfer angle in the cross-section at the nose cutting edge is smaller than the chamfer angle in a cross-section at the wiper edge.

3. The cutting insert according to claim 2 , wherein the peripheral land follows a substantially straight line in a cross-section through the cutting insert.

4. The cutting insert according to claim 2 , wherein the peripheral land has a continuously varying chamfer angle at the corner portion.

5. The cutting insert according to claim 4 , wherein the chamfer angle in a cross-section at the nose cutting edge is smaller than the chamfer angle in a cross-section at a first wiper edge.

6. The cutting insert according to claim 2 , wherein the peripheral land in a plan view has a substantially constant width.

7. The cutting insert according to claim 2 , wherein the cutting corner comprises a first wiper edge being defined by at least one radius and a second wiper edge being defined by at least one radius, the radii have different points of origin.

8. The cutting insert according to claim 7 , wherein each first and second wiper edge has a continuously varying chamfer angle.

9. The cutting insert according to claim 2 , wherein the cutting insert partly or completely is comprised of cubic boron nitride.

10. The cutting insert according to claim 1 , wherein the chamfer angle in the cross-section at the nose cutting edge is smaller than the chamfer angle in a cross-section at the wiper edge.

11. The cutting insert according to claim 1 , wherein the peripheral land follows a substantially straight line in a cross-section through the cutting insert.

12. The cutting insert according to claim 1 , wherein the peripheral land has a continuously varying chamfer angle at the corner portion.

13. The cutting insert according to claim 12 , wherein the chamfer angle in a cross-section at the nose cutting edge is smaller than the chamfer angle in a cross-section at a first wiper edge.

14. The cutting insert according to claim 1 , wherein the peripheral land in a plan view has a substantially constant width.

15. The cutting insert according to claim 1 , wherein the cutting corner comprises a first wiper edge being defined by at least one radius and a second wiper edge being defined by at least one radius, the radii have different points of origin.

16. The cutting insert according to claim 15 , wherein each first and second wiper edge has a continuously varying chamfer angle.

17. The cutting insert according to claim 1 , wherein the cutting insert partly or completely is comprised of cubic boron nitride.