G0752 Chuck stuck good and hard!

[Perplexed]

I've never seen a chuck this tight before.
Silly as it might seem, have you considered the fact that it might have a lefthand spindle thread?

Certainly is stuck but good. So much that I considered left-hand threads, a hidden locking screw somewhere, or even just rust. But I went by the manual that came with the lathe, and it specifically said, “Turn the chuck in a counter-clockwise direction to remove.” And according to the manual, there are two locking tabs, which I had already removed, and that’s it. Then unscrew the chuck to remove.

I shone a flashlight everywhere I could, but no sign of any rust, either. Heck, I used so much penetrating oil that I’ll probably get a stream of the stuff pouring out of the spindle whenever I manage to remove the chuck.

 

[fitterman1]

Then the last option i see for you apart from dismantling is this.
Get or make the previously mentioned pin spanner and fit it to the hole on the spindle and cut a piece of wood to fit between its back and the ways of the bed.
Make it a jam fit or close to.
Put a thick wall tube of good fit over its handle upto the head.
Cut some 4 x 2 to length so that when the c spanner is horizontal and underneath the spindle,it reaches to the floor and supports the tube.
Get some steel hex bar of the biggest size that will fit right into the chuck and tighten well.
Get some stillsons that large they're unbreakable and attach to said hex bar.
Put an extension pipe on stillson handle.
Make sure you protect the ways sufficiently to prevent damage.
Be careful how you orientate the stillsons, if you have a horizontal pin spanner bar, have the stillsons bar a little higher, this will prevent you tipping the lathe over unless its bolted down.
Lean on that bar until something gives.
Bear in mind the weakest link is the pin spanner and that may let go first. It needs to be solidly fitted.
If this doesn't work take the chuck and spindle out together and send to Grizzly and ***** hard about getting the chuck off.

 

[Long Roof]

Did you check to see if there are set screws on the backside of the chuck that need to be removed to allow unthreading? I think they are to keep the chuck from unthreading if it is run in reverse. Mine has them.

 

[fitterman1]

Yes, he's done that.

 

[fitterman1]

I think Purplexed's problem is a combination of a tight unlubricated thread which may have galled itself together ( think friction weld ) and the register and chuck mating faces having an incredible amount of sticktion.

 

[Bi11Hudson]

'Way back in the dark ages when I was just starting with industrial electrical work, I ran a lot of rigid conduit. I mean a LOT, as I was one of the younger guys in the shop and could contort to fit the old(ca1896) mill building. Mostly 3/4 inch rigid which equates to 3/4 inch schedule 40 galvanized water pipe. I got so strong in my hands I could assemble a conduit run by hand that needed a pipe wrench to undo. That was a long time ago, but the memories are still there.

Which brings me to the problem at hand. There were instances of 3/4 rigid laid directly on a concrete floor where it could be run over by forklifts and the like. A trick I soon learned was to attempt to tighten the joint before loosening it.. Not much, just enough to get it to "creak" or squeel once. On old galvanized pipe, fasteners, most any super tight connection, it did help. Even the longest pipe wrenches would find things easier. It was an old school millwright that showed me the trick.

I don't say it will solve your problem, but it would be worth a shot. If it didn't work, you only wasted a couple of minutes.

.

Galling was the idea behind tightening it slightly before unscrewing it. I stand by my earlier comment to that effect. My machines (2) have threaded spindles and no way to reliably lock the spindle. There is the backgearing on the big machine, a good way to break a tooth on the gears. The impact wrench will play well here. Preferably with a piece of hex stock but a bolt tightened up in the chuck will serve almost as well. An air driven impact wrench is better, but there is a hand impact wrench used widely by motorcyclists. Just be sure to strike the wrench, not the machine. Try one blow to tighten then several to loosen. Use a heavy hammer, a rubber hammer won't cut it. I have a six pound drilling hammer for that purpose alone. Don't bother trying to lock the spindle, just shock it loose.

.

 

[lordbeezer]

Was referring to a air impact. Might should have said. Problem with using a bolt it will move a little taking shock value away.

 

[pdentrem]

Use a large coupling nut with impact gun, air or electric. No need to lock the spindle likely, just the frictional losses in the drivetrain should be enough.
Pierre

 

[tq60]

Old school is to place chuck key in and tap that.

But given all you have done something else.

Get a bar bell weight or an automotive disk brake rotor.

Find the biggest diameter piece of metal that you can grab with the chuck and get it as tight as you can.

Get a Worn out or ugly brazed carbide and place in your tool holder upside down.

Adjust height so it bites, does not need to be on center but close as possible.

Run in slowest speed REVERSE and take assorted cuts.

Sent from my SM-G781V using Tapatalk

 

[SLK001]

You need to make one of these. Using it to grip the spindle, you should be able to remove the chuck. You'll need to modify the dimensions to fit your lathe and everything can be made with a lathe, a hacksaw and a file.

If you can grip the outside of your spindle at the rear of the headstock, a more rough tool could be made with a 4" x 4" piece of 1/2" aluminum. Drill a hole in the center of the piece the exact size of your spindle at the rear, then drill two holes on either side from the side of the piece (not the face) for a 5/16" tap (these two holes will be used to hold the two pieces together once cut). Cut the piece in half, cutting across the two tap holes, then open up the two holes on one piece for a 5/16" clearance and tap the two holes in the other piece. Now get a piece of flat bar and drill two clearance holes for a 5/16" bolt at one end, spaced at the same distance as the two bolt holes in the 4" x 4" piece. Mount this contraption on the end of the spindle and tighten the 5/16" bolts (through the flat bar). Using this and a bar across the face of your chuck, you should be able to remove your chuck.

If this doesn't work, you may want to consider turning the chuck backplate off the spindle (reduce it to dust).