One day I found the work held by the collet was eccentric. It was even visually clear. I checked the Morse taper and found a couple of dents provably made by chips. I corrected them by a rotary tool with rubber stone.


I checked the taper with a dial indicator to see there were no peaks.


Still the eccentricity was measured as large as 0.1mm. There must something causing this.


I found the inside of the collet holder was so dirty. I never cleared this part in the past.


I cleaned it up and the eccentricity was reduced to about 0.01mm. It is acceptable. It was a fault caused my laziness.



inserted by FC2 system