CNC lathe machine jobs: Outer ring surface roughness not good

Problem: Not just the outer ring surface, the screw thread and the end face, all of the roughness is bad with burrs, but the screw pitch, length and diameters are all in tolerance range. (From http://www.CNCmakers.com)

Normally we could check below for these symptoms:

1-      Is the full indicator movement of the spindle motor too big?

2-      The cutting tool is abraded?

3-      Is the output torque of the inverter smooth or not?

4-      X and Z axes are in good conditions?

5-      Machining processing technic is proper or not?

In this case we checked the full indicator movement of the spindle motor is 0.2mm, which caused the problem, change the spindle motor bearing, problem solved.