Replacing the broken bearings in my pm1440gs headstock

I took a look at my manual and it shows those as caps with a oring.
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I’m guessing they weren’t lubed in the installation plus coated with paint after Assy they will probably be a bear to get moving. Spray them down with some penetrating fluid.
 
Thanks Cadillac. Yea that's what I've been looking at the past couple days lol. Pm glossed over it as if a trivial detail when I asked for a procedure. I have, tapped, bumped, cleaned the edges, screwed the cap screw in all the way to bottom it out and hope exert pressure from inside... placed a 10lbs barbell weight on the slide of the bearing puller... I'll try the co2 next. Liquid wrench is soaking...
Thanks for the help. Its keeping me in the right frame of mind and on focus on how to approach this.

WARNING!!! Chinese machines are wonderful bargains, and good machines if you get a good one, else they are full time parts kits lol
 
another approach to pulling that cover out - make a ring with an ID a little larger than the cover. Cut it to fit next around the spindle. Get a piece of plate with at least the same OD as the ring and nice'n'thick. Drill a hole in it large enough to fit the screw through. Assemble it over the cover, thread a long enough bolt through with a couple of copper washers under the head. Tighten down as much as you dare, then leave it over night. Maybe play a MAP torch around the outside of the ring for a bit, maybe on the bolt itself. Tighten it a bit more, then leave it. If you strip the threads on the cover, drill it out and tap it to the next size.

If none of that works then at some point you're simply going to have to cut/ chisel the thing out and make a replacement. Annoying but not particularly difficult. Good luck!
 
I guess this is where a pressure lubed headstock is better. Guaranteed lubed instead of the splash/drip system we have and would help to flush contaminate out of crucial areas.
 
I guess this is where a pressure lubed headstock is better. Guaranteed lubed instead of the splash/drip system we have and would help to flush contaminate out of crucial areas.

Until the pump quits and you don't catch on until it's too late! :eek:

I've had my share of Chinese 'kits', and managed to make some work really well and others not so much. Best of luck with this @richl.
 
Think I'm making a 2000lbs piece of scrap. This is not going well at all. Going to stop for the night. Frustration level high. Maybe try and weld a clip to it tomorrow.
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"Broken bearings " in 30 hrs............Id like to see that...................Unfortunately beginner diagnosis is not reliable,and a perfectly good bearing will often make some noise due to particles in the oil.......and regrettably Chinese lathes do have plenty of particles in the oil........however its either sand or cast iron swarf,and neither will seriously damage hard steel rolling elements..........Please dont break everything to pieces with amateur efforts to remove one $5 ball bearing.
 
If that was me, I would thread a few of those holes and and use some bolts to pull that sucker out.
 
Bearing is right behind it, not able to run a tap.
Thanks for those kind supportive words john k.
The bearings were toasted. Whether you believe it or not does not matter to me.
 
Looks like you’ve given a good effort that’s for sure. Maybe try to spin the cover by using a punch and just try to get it to budge. Has it moved any? Looks like it’s moved in if anything? I would probably stay away from a torch.
What happen with the center hole? It might be best to make a puller like suggested above with a larger id so you can apply constant pressure on cap by backing out the screw threaded in the center. That center hole will be your best best applying equal force.
Soak it overnight give it your best tomorrow you will get it. Best of luck
 
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