What is the meaning of the so-called CNC lathe?
So that the knife is due to a variety of objective factors caused by the linear size of the product deviation, there are many reasons, the above two also said almost, but in the cutting as much as possible to avoid and make the knife is due to various objective factors
There is a machine tool screw itself has a gap, will let the knife.
The so-called knife, that is, your processing system (including the lathe body, turning, the workpiece) is not rigid enough, due to the impact of cutting force, causing deformation.