main reason

Cutting edge is too large; high-speed cutting thread, the cutting thickness is too small or the direction of the chip to the tilt discharge, the tooth surface has been processed tooth; the workpiece surface of the workpiece; Rigidity is poor, and the cutting amount is too large; turning tool surface roughness difference.

Solution

Cutting with high-speed steel cutting tool should reduce the cutting speed, and the correct choice of cutting fluid;

Increase the shank section, and reduce the handle extension length;

Reducing the radial rake angle;

High-speed steel cutting thread, the last knife chip thickness is generally greater than 0.1mm, and the chip along the vertical axis direction of discharge;

Choose a reasonable amount of cutting;

The surface roughness of the cutting edge should be 2 - 3 grades smaller than the surface roughness.