[OT-CNC]

Hi,

Has anyone successfully repaired/rebuilt a varigrip collet closer? Mine is leaking air as expected. I need to replace the bearings in the rotary union and perhaps re-do the bronze bushing. Is there a trick to pulling these bearings? I see a shoulder on the aluminum hub, is this perhaps a threaded on retainer? I can't seem to remove it....the rotary union is currently removed from the draw bar/air cylinder. My primary interest is removing the bearings. Any suggestions?
Also, how are current modern rotary unions sealed and capable of sustaining high rpm?

[OT-CNC]

Okay, got the bearings out. The aluminum hub is sold. I used a map torch on it for a bit. The expansion was enough to help drive the bearings out. I made a simple tool to engage the bearing from the inside on the inner race. Just a bent 1/4 steel rod with the end ground to touch the bearing. A gentle blow with a brass bar on the tool in a few spots is all it took to get it out.
As suspected, the bronze inner bushing is worn.
Has anyone come up with a clever sealing method for this rotary union?

[lcvette]

Did you ever resolve this? I have a cobra42 hardinge lathe with the same leaking air issue and looking to find a solution other than buying a multi thousand dollar replacement. thanks in advance!

Chris