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Stuck chuck Leblond 13 Using custom spindle wrench (Clemson style) slipping thoughts?

chippinchunks

Aluminum
Joined
Oct 11, 2016
Location
San Diego
HI all. Stuck chuck on my Leblond 13 Regal Round head. Threaded spindle. I've tried various methods, cheater bar clamped across chuck, running lathe in reverse & turning off so it bumps, heating backing plate while hammering, penetrating oil etc. I made a custom spindle wrench out of aluminium similar to "clemsons method" seen on another thread here. My problem is the wrench is slipping on the spindle shaft. The bore of the wrench is the same as the od of the shaft but I removed .125" from each side (inside of the 2 halves) i figured it would be enough to grip it. I used 3/8 × 16 bolts. Alumimum plate is .75" thick. I've tried pine tar on the shaft, thin rubber self adhesive tape used for patching holes in radiator tubing, cork & no matter how hard I tighten the bolts the tool slips when force is applied. Do you guys think brass shim stock, aluminum foil or maybe glazing the inside of the tool & spindle shaft with loctite & letting it cure, maybe larger bolts? I can probably get 1/2 inchers in there. I know i probably need a bigger bar! No pun intended but it was late last night when i got it all together. Let me know

As always thanks in advance
Martin
 

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Tough one, but I’d say careful with heat and hammers! Not on a spindle unless it’s already well F’’’ed. Don’t use motor power unless you want to break off some gear teeth.
Skip all the junk in there trying to increase grip, it’s not a baseball bat. dry metal to metal is probably better, all that crap is acting as lube I think. use a solid bar instead of a perforated tube as a lever arm.(your bolt “clamping force” is wasted just going to splaying out that thin tube, limiting your pinch) Good luck
 
You want the clamp wrench bore slightly undersize. .010 to .020 under i would think. Better clamping capability i believe.
 
powdered rosin is what gunsmiths use for tough jobs........I also think the clamp should be steel....ally ones are no good on tough barrels.....steel with susbtantial bolts,say 9/16 unf or 5/8unf HT ,with grease on the threads but never on the gripping surface.....clean the surface with acetone.
 
Steel on steel for the clamp would be better, and I would split only one side of the block. Another option is to take off the headstock cover, and see if there is another feature of the spindle you can grab, like a splined area. You'd have to be careful not to damage anything critical, of course.

allan
 
Good tips above. Don't hammer. Repeating - all of those goopy tapes and stuff you are applying for grip will liquify and slip under extreme pressure. Consider the lever arm length at the contact interface - the shear force is tremendous. Aluminum on steel is also slippery. Keep it in neutral or between gears.

A common trick to increase grip on screw heads etc is to apply valve grinding compound. That may just brinell into the aluminum under the shear force.

Oh yeah, work smarder, not harder :)
 
I have removed rusted on face plates and chucks from wood lathes with 1 1/4 inch threads by:

Warm chuck with heat gun or hair dryer, soak front and back sides of thread with PB Blaster or your favorite, using small brass hammer tap, tap, tap, close to threads, add PB B. Let set overnight.

Next day do as above, lock spindle as you have and with suggested mods as above. Mark spindle and chuck plate to see movement when attempting to unscrew. Put steel bar in chuck sticking out about 18 inches, put a piece of wood on lathe bed for bar to hit in case chuck comes loose, heat chuck as warm as you can get with heat gun, more PB B. With 3/4 - 1 inch steel rod whack the bar sticking out of the chuck with all your might. Check marks for movement. No movement, one more whack.

If movement, tap, tap, tap, on the bar until free.

If no movement, more PB B and tap, tap, tap, let set overnight and repeat. Add hunk of dry ice inside spindle bore if available.

The light tapping helps get the PB B into the tight places. The hard whack shocks the whole connection to break it loose. A big hex in the chuck turned with a big impact wrench would do the same. You want a sharp fast shock as opposed to a heavy slow thud.

Any lube that gets into the tight places will work, liquid wrench, auto trans fluid, whatever "mouse milk" you favor. For me, PB Blaster works better than WD 40, and is more available than some other favorites.

Keep in mid the register between the spindle nose and the back of the chuck is as important to get slippery, if not more so, as the threads.

Heating and cooling and more juice with overnight rests will eventually get most things apart.

Paul
 
One simple trick to remove seemingly stuck chucks with threaded spindles is to cut a piece of 2x4 spanning more or less the distance between the back ways and the height of the spindle bore.
Mount the external jaws on your chuck and leave them as open as possible.
With the lathe in neutral, spin the chuck backward as fast as you can, having each of the jaws, one at the time, slamming against the piece of wood, bringing the chuck to a sudden stop. Do at most 8-10x per session, spray more penetrating oil and repeat 2-3 more times.
The inertia of the spindle and bull gear should help loosening the threads, and the energy involved is not enough to cause any damage in the headstock.
So far, for me it worked in all but one case. And, in that case (a very rusted lathe heading for the scrapper, from which we wanted to recover any possible thing), no other method worked.

Paolo
 
Thanks for all the input. The friction chart is definitely a good references. I'm going to upgrade the bar to a longer non perforated bar... hopefully solid if I can find one today. Upgrade clamping bolts to grade 8 & purchase 1/2 inchers just in case. I looked inside the headstock last night & I didn't see anywhere else I could put a tool or shim gears. Spindle OD appears to increase to approximately 2" inside the headstock so it would require me to make another clamp. I tried a piece of brass shim stock around the shaft (approximately .02" thick") last night. I installed clamp over the shim stock & cranked on the bolts as much as I could. It did grab better than anything I had tried previously. I'll look into to getting some powdered rosin as well. I'll keep you posted!

Thanks again
Martin
 
Good to better hold the back as you seem to be doing. Agree 1/2" thread will likely double the hold. How are you holding the front (chuck). fab-up a spanner might do, big adjustable on a jaw, Have seen guys put a bar across two jaws but don't think that is good for the chuck, chuck up a large hex or square stock and a big wrench on that, use a big torque wrench on a held hex or square stock held in the chuck. Or just locking the chuck in place and turning the spindle back end?

likely it is too tight to the spindle nose face so perhaps to cool the chuck with some dry ice.

Could be rusted to the thread if machine sat out doors..guess that is what you are using WD or the like for.

I had a stuck chuck and gave up on it, the next spring It came off easy, yes It spent the winter in an un-heated space..
 
I've found that Kroil works better than PB Blaster. Heat it with hair drier and soak the area with Kroil let cool, Keep doing it as often as possible, after a couple of days try removal. Aluminum is not good to make the spindle clamp use steel and nothing with lubricant in it. Talc power works!
 
Sounds like some trunk monkey spun the chuck on... I have removed chucks from my 15" trainer by opening the jaws or one jaw of a four jaw and striking with a lead mallet...Put the head stock in the lowest gear and hold all of the backlash out of the gears before you strike the jaw in the direction to remove....That is a coarse thread 2 1/8 - 5 if memory serves and it will turn loose pretty quick or it has with me using this method...I have had two of these lathes and never had a problem removing chucks this way.. Ramsay 1:)
 
powdered rosin is what gunsmiths use for tough jobs........I also think the clamp should be steel....ally ones are no good on tough barrels.....steel with susbtantial bolts,say 9/16 unf or 5/8unf HT ,with grease on the threads but never on the gripping surface.....clean the surface with acetone.

Use to remove and install large ring Mauser 98 barrels in a clamp lined with soft lead with powdered rosin between the lead lining and the smooth barrel...No damage done in this manner.. Ramsay 1:)
 
Well,a guy i worked with removed Mauser 98 barrels by simply bending them to a right angle.....but you try removing an Eddystone barrel,or a Ross M 1910......I use steel blocks clamped in a 60 ton press,and a 6ft bar....and even then the barrels sometimes slip in the clamp...........edit...have you tried dry ice in the spindle,and strong heat...a big oxy /act heating tip at max flow.Speed is the key,long heating is useless.
 
Thanks for all the tips & advice everyone! Here's a quick update. Lots of progress on clamping force of the tool but the backing plate will not budge. Upgraded the clamping bar to a 1.25" solid square tube. It's 4 feet long so it can reach the floor. Clamping bolts were increased from 3/8 to 7/16. I left the brass shim stock around the spindle & placed the aluminum clamps around it. I decided to remove the chuck off the backing plate so I can get closer to the threads on the spindle. I used some PB & used some heat from a heat gun. I mounted piece of scrap flat bar across the face of the backing plate & used a 6 foot steel pipe for a cheater bar. This set up gave me quite a bit of leverage. Clamping force has increased substantially but the clamp is still slipping even though it takes quite a bit of force now. I tried heating & light taps while applying force but she still won't budge at all. I feel like I'm almost there with the clamping tool. I should of tsken the advice on using a solid steel clamping bar instead of hollow square steel tube. The bolts crushed the tube slightly. Tomorrow I'll use the other side of the bar & ill turn some steel spacers to put inside the bar. This should keep the bar from collapsing & give me a little more clamping force. I'll do this & try the rosin. Hopefully these 2 things will give me more grip & no slip. Which type of rosin should I use? I've seen metal & wood (I believe). Here's a pic of the set-up. I feel like I'm almost there. Lots of progress today. Thanks again everyone!

Martin
 

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So you already read the advises. LeBlond 13" with threaded spindle. Way out of this league but weren't these lathes capable of rapid reverse? There was a key or actually an..L tapered spindle.When you back off the collar it is close to the head so you may think the spindle is threaded but it isn't.

I'll regret this post but we need to read about the different spindle designs and dead certain about how to attack it. In Particular is the register which has been addressed. So damn tight ( for a reason once) . Again, the great advise of heat and cool. There are tools for removing pipe from fittings. They could go midway into the unfinished area of the spindle and the spindle be contained by fact there is serious gear around it. That puts the torque much closer to the chuck. These tools are sort of old now but the external jaws expand into the internals under ... dang . stop .
 








 
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