Thread: No luck removing chuck

If that STILL doesn't work, then go down to your local electronics store, buy a can of freeze spray, heat as above and dump the can in the spindle bore. If you have the backplate up around 100 C and the spindle around zero or below, it would surely have to come off!

Pete

Originally Posted by Pete F

If that STILL doesn't work, then go down to your local electronics store, buy a can of freeze spray, heat as above and dump the can in the spindle bore. If you have the backplate up around 100 C and the spindle around zero or below, it would surely have to come off!

Pete

Yes I have a can of that freeze stuff here already .

I only have a small LPG torch ..it does heat up the hub , but takes ages .

I might try screwing the 3 long bolts back into the hub and place a lever across them . They may bend , but they are only common socket bolts , easy to buy .

At least now I have more access to the hub And the chuck isnt acting as a huge heat sink ,

I was thinking the same thing Mike. I use a heat gun for this type of thing, can't recall the model, but I think on high it puts out 700C (????), anyway it's surprisingly hot.

I wondered if you could put the chuck on loosely, so it wasn't really against the back plate, heat the backplate, tighten the bolts, throw the freeze down the bore, then whack away? The only reason I'd persist with the chuck is because I think it may give you more "persuade" options. Any way you go, once you use freeze you need to work quick, in contrast the rest will hold heat well.

Good luck! I have a good feeling you'll get it this time

Pete

Hi Mike,
I'd be tempted to make up a plate about 10mm thick that picks up on the three holes, weld a big bolt in the middle, bolt it to the backing plate and try the rat gun again. With out the weight of the chuck you might have more luck.
Failing that you can weld a bar to it and get the big hammer out.

Does your freezing spray have a penetrating lubricant? or is plumbers freezing spray?

Stuart

Originally Posted by Stustoys

Hi Mike,
I'd be tempted to make up a plate about 10mm thick that picks up on the three holes, weld a big bolt in the middle, bolt it to the backing plate and try the rat gun again. With out the weight of the chuck you might have more luck.
Failing that you can weld a bar to it and get the big hammer out.

Does your freezing spray have a penetrating lubricant? or is plumbers freezing spray?

Stuart

Hello Mike, as the others have said, heat's the go. You can even use a hair dryer. You have to break the bonds on the thread, Heat it, give it some short sharp taps all around with a hammer, then try and undo it with an extension bar. Quite often a strong slow turning with an extension bar is better than shock hits such as an air hammer in these circumstances. It's all about breaking the bond in the thread: heat, then cool, and then slow strong turning. Good luck with it.

Also to be aware of with heat in this situation ie, the hub is also tight against a flat mating surface on the gearbox end and it is being held that way by the flanks of the thread.

Heating causes the hub to grow slightly in both diameter and length so heat has the potential to be actually making the hub push harder against the flat mating face in one direction and the flanks of the thread in the other direction. If you give it heating and cooling cycles as I mentioned earlier and try removing it between each cycle when all is cool.

Good luck with it.

Cheers.

If I'm not right, then I'm wrong, I'll just go bend some more bananas.

By all means use heat if you wish,I think in the use of heat a decent type of heating medium should be used,either an LPG/OXY torch or OXY/ACET torch.

Hard to tell from the photo but there appears to be a lot of wall section to be heated.

Do you have the resources to buy or make another backing plate? If it was giving me that much grief, I’d fire up the lathe and turn it off. Little risk of damaging any thing if you know what the thread is.

Now that you can see the end of the thread, once you get close to that, it will free right up.

Less dramatic means, If you know the thread diameter, you could drill a hole in the journal, where the slots are. You have to measure it, so you break through into the thread, tap the top M6 or 1/8 BSP, and fit a grease nipple. Give it a decent squirt of grease. The clearance in the root / crest of the thread will allow grease to encircle the thread journal. A good gun will go 10,000 psi. An Enerpac with oil will do the same thing.

I’d second what the other boys have said about heat, if your doing that, you have to dump the heat in fast, so the backing plate heats up and not the spindle, but as noted, that might make it tighter on the shoulders.

Phil.

Now you can get some penetrant in the thread.
You can also get an indicator on the spindle bore.

Originally Posted by Machtool

Do you have the resources to buy or make another backing plate? If it was giving me that much grief, I’d fire up the lathe and turn it off. Little risk of damaging any thing if you know what the thread is.

Now that you can see the end of the thread, once you get close to that, it will free right up.

Less dramatic means, If you know the thread diameter, you could drill a hole in the journal, where the slots are. You have to measure it, so you break through into the thread, tap the top M6 or 1/8 BSP, and fit a grease nipple. Give it a decent squirt of grease. The clearance in the root / crest of the thread will allow grease to encircle the thread journal. A good gun will go 10,000 psi. An Enerpac with oil will do the same thing.

I’d second what the other boys have said about heat, if your doing that, you have to dump the heat in fast, so the backing plate heats up and not the spindle, but as noted, that might make it tighter on the shoulders.

Phil.

Slow heating is as others have said, useless. The heat has time to get to the spindle and therefore achieves nothing. You need to heat FAST and that means an oxy torch with a big tip. Cooling the spindle at the same time would certainly help.

I'd bolt a chunk of 100x12 at least 600 long to the backplate using the bolt holes & high tensile bolts, then smack it *hard* with a big hammer, say 3 kg sledge, with the spindle free to rotate so no risk of breaking gears. Put a big chunk of timber on the bed to cushion the blow when the steel slams down as the backplate comes free, you don't want to ding the bed.

This is how I broke loose a 28" face plate off of my Smith-Drum lathe. It had been there for 20+ years. Being gentle achieved nothing.

If that doesn't work, Phil's suggestion is next. Just turn the thing off and make another one.

PDW

Originally Posted by Stustoys

Hi Mike,
I'd be tempted to make up a plate about 10mm thick that picks up on the three holes, weld a big bolt in the middle, bolt it to the backing plate and try the rat gun again. With out the weight of the chuck you might have more luck.
Failing that you can weld a bar to it and get the big hammer out.

Does your freezing spray have a penetrating lubricant? or is plumbers freezing spray?

Stuart

I was thinking along the same lines Stuart , a plate bolted to the hub with a large hex head on it and the windy gun .

But all of the suggestions are worthwhile . I'm still cautious of using heavy hammers . The gears in the head are hardened steel I believe , not cast iron .

I am about to give it another attempt .

The freeze stuff I have is the LOCTITE brand .

The neighbour has a oxy set ..I can use it to shock/fast heat the hub if all else fails . The method would work no doubt , but his oxy set is heavy with large bottles , not easy to transport

MIKE

If you attempt to heat it I would suggest to spot heat it only,at least this will contain the amount of heat going into the fitting.
You might have to start another thread in the welding section on a bottle trolly.

I think the main issue is the spindle can not be held rigid enough to crack the rusty seal.
I reckon I would make up clamping dog vice with four large bolts to close it for the back end of the spindle that lock down on the spindle and with a welded or machined on extension that engages against the casing some place. Clean the rear spindle extension well with emery paper and then degrease it and the dog vice with acetone or shellite . Then powder the surface with fine rosin and clamp the dog vice on real tight . That should stop any movement in the direction of removal.
Then make up a plate that bolts to the same bolt holes as the chuck that has 50 mm square bar welded to it that stick out so you can slip a long piece of square tube over it or hit it with a big hammer without the tube on.
Once all that is in place chock up the spindle from underneath with steel blocks and wedges so all slap in the spindle bearings is taken out towards the top don't go crazy just firm it up to take out any chance of damaging the bearings . Then weld some strap across the steel wedges so they don't slip out .
Then soak in as much wd40 as possible over a few days . Protect the lathe ways with some sheeting or boards . Then cross yourself , heat the fu*ker up and give the square tube a big reaf down . If it still don't crack then remove the square tube and hit the square bar with a big hammer .
If that all fails then it will need to be machined off as suggested above .

When you finally get the Spindle thread showing what will be your intension for further fittings for the Spindle.

Hard to tell from the photos but it looks as if the threaded section that screws onto the Spindle is about 2" long if not longer.

If you were to fit Backplates to your tooling there would be considerable cost in the material.

Have you considered making up a spacer to take up some of the length of the Spindle thread,around 1" should be plenty.

At the end of the Spindle where this backing plate locates,your photo gives the impression that there is a considerable gap between the (nut) and the Spindle Register.Have you been able to get a feeler in there to see if the (nut) is hitting on a register.