I finally got my rebuild done. Photos show original machine, disassembled and stripped for painting, some painted parts and completed machine. Controls have been replaced with a USB breakout board running on Mach 3 and a TECO VFD on the spindle. I rebuilt the spindle motor and replaced most of the bearings in the head (spindle bearings had been replaced by the previous owner). Cleaned and re-greased X and Y thrust bearings (have new ones on hand)and replaced all oil meters and tubing. Table surface reground. Ways are in pretty good shape. The head stays within .001" everywhere on the X+, Y+ quadrant of the table. There is no backlash on any axis. The only concern I have is with spindle runout.
The mill has an Erickson QC30 spindle. I got several tool holders with it. They vary in runout from .001" to .008". I did a lot of measuring at different points on the holders and with bits in them. I am not too happy. Then I set up the dial indicator to reach up inside the spindle and measure directly on the 30 degree wall of the spindle. I was thrilled to find that the needle on the indicator did not even move when the spindle is turned. Runout is less than .0001 (less than one ten thousandth). I also checked the bottom of the QC and it also runs true to .0002".
My question is this? Why won't the tool holders and bits run true if the spindle is running true? How do I check to see if the problem is poorly made tool holders or if they are just not seating right in the spindle? The tool holders I got with the machine are marked APT USA and Kennametal.
Ron
The mill has an Erickson QC30 spindle. I got several tool holders with it. They vary in runout from .001" to .008". I did a lot of measuring at different points on the holders and with bits in them. I am not too happy. Then I set up the dial indicator to reach up inside the spindle and measure directly on the 30 degree wall of the spindle. I was thrilled to find that the needle on the indicator did not even move when the spindle is turned. Runout is less than .0001 (less than one ten thousandth). I also checked the bottom of the QC and it also runs true to .0002".
My question is this? Why won't the tool holders and bits run true if the spindle is running true? How do I check to see if the problem is poorly made tool holders or if they are just not seating right in the spindle? The tool holders I got with the machine are marked APT USA and Kennametal.
Ron