Gamfior E13666M Spindle Repair

This Gamfior E13666M spindle had been put through the paces in a high production Fidia 5-axis machining center. It had many worn parts as you can see from the evaluation below. It also has a specialty shaft that needs to be worked on by experienced technicians that have grinding capabilities on site. If this spindle is not assembled to exacting tolerances, tool retention force, and accuracy, it can be compromised causing poor part finish and potentially dangerous conditions for the operator.

CHALLENGE

Our customer sent in this Gamfior E13666M spindle complaining of excessive runout.  When it arrived at Northland Tool and Electronics we measured 10 microns of runout on the taper and 2 microns on the face.  We also noted that when our test bar was installed it showed it hitting the face before it makes taper contact, this would allow tooling to rock.  Then the critical dimensions (bearing journals, housing, taper, etc.) were measured and we found a few issues.  First, the rear shaft journal was out of round.  Second, the drawbar was worn from the bellevilles.  Lastly, the rear housing was oversized +14/+16 (ISO is +/-6.5).  It was also noted that the gripper fingers were worn and that there was no rear sensors and no actuator supplied for the rebuild.

SOLUTION

The following actions were performed on this Gamfior E13666M spindle:

• Clean, inspect overall dimensions
• Replace bearings, bellevilles, bolts, and orings
• Replace grippers
• Grind, chrome plate and finish grind (GPG) the taper
• GPG the drawbar
• GPG the rear shaft journal
• GPG the rear housing

RESULT

After reassembly of all components, adjusting bearing preload, and undergoing break-in and testing procedures, this spindle passed our final quality inspection before being returned to our customer with a 1-year warranty.