Very Stuck Chuck on 17" round head

[Ray C]

Here, take a look at this picture. (BTW: You can click the PDF image and use the mouse buttons to see 3D).

You could just use a long bar w/o the L-shape but if space is a limitation, using the L will give you the same torque. Also, you can use the tailstock and a plate to hold the bar into the slot. While somone is putting force on the bar, somebody else should be whacking the bar with a hammer a few inches from the chuck where its inserted into the slot.

Another thought. You can probably make, beg or borrow a chain wrench. The one I have only wraps around 8" bar/pipe stock but they come much bigger. I'd be inclined to make one if I needed bigger.

I know this sounds crazy but, is there any chance it's a left hand thread? It defies all common sense but, I don't profess to know everthing about every lathe that was ever made...

 

[lindse34]

OK, now I see why you would do that with limited space. Though it may be hard to apply force perpendicular to the axis of rotation if the second bar is very long. I had the second bar in my mind rotated 90 degrees about the x axis which would make little sense. Fortunately there is room to hang a 20 foot bar off the thing...Now that I think about it there is one out back....

Pretty sure its right hand. I can see some of the threads at the end of the spindle and they are right hand.

Got the clamp made tonight, hopefully adapter plate on the mill tomorrow night.

-Matt

 

[Ray C]

Well, I sure you you get it off. Only other minor thoughts I have are to pack the spindle with some ice and heat up the chuck. And if that long bar bends, a chain pipe wrench wrapped around the chuck would help. If you make one out of regular chain instead of the bicycle/link chain, you could probably put some rods through the slots that go through the chain links. You could weld-up a pipe chain in a jiffy. I suspect you know what I'm talking about but if not, I'll take a picture of my pipe chain wrench and how I'd make one if needed.

So, have you got someone around to bang on the leverage rod with a hammer? My guess is that thousands of impacts from interrupted cuts is what caused this mess and when this happened to mine it was the hammer blows (impact) that did the trick.

I'll stay tuned and keep the fingers crossed.

Be careful and good luck.

 

[Dbingen]

I have a Sheldon that had a stuck 3-jaw. The 4-jaw looked like it hadn't been on in 20-30 years. I used penetrating oil, heat, impact, etc for over a week, with no success.

I finally chucked a 3/4" by 1-1/2" alum. Bar about 3' long at right angles to lathe axis. I then used a piece of brass stock that fit closely to the bull gear to wedge it in place. I set the bar horizontal to the lathe and hung about 125-150 lbs. on the end of it, thinking I'd let it sit over night. While placing the weight on it, the chuck came loose!

Now, I never place a chuck on the lathe without carefully cleaning it and putting a little oil on it. I always bring it tight by hand, too.

...David

 

[lindse34]

Well it came off). After finishing the spindle clamp I thought I'd try it with the 3 jaw on one more time. With the better spindle clamp we could really hang off the pipe wrench. After the talk of hitting it, I welded a piece of angle iron to the spindle we had chucked so we could use a maul on it. And after about 15-20 strikes it broke loose. To my surprise the threads had oil on them, but I had been dousing it the last 5 days with penetrating oil so maybe that finally did its job. Good to be done with this. Thanks for all the ideas.

 

[swatson144]

Congrats and I am glad it came out in the wash.

Steve

 

[Ray C]

Just in time for Thanksgiving as you had hoped! :thumbsup:

 

[Bill C.]

So today I was leafing through the manual for these lathes that is posted on this site and noticed the 17 inch is supposed to have a L0 long taper key drive. After questioning my memory for about 5 minutes I went to the shop expecting a heaping of humble pie coming my way, but I'm pretty sure its a threaded spindle. I had made this conclusion before based on the 4 jaw that came with it but then I realized maybe it was just thrown in the deal and not actually for this lathe. At any rate I took some pics of the spindle and ironically the threads in one spot were chipped enough to look like a key way but after cleaning it it's just a chipped thread. Which may point to other problems.... Actually I kinda wish it was L0 that would probably be a lot easier. From what I measured I think it is 2-3/4"-8 thread. So I don't know if they sometimes came with that instead of L0. This is the lighter duty version of this lathe so maybe that has something to do with it.

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So Ray, for a bit I was thinking your question about spindle type was very relevant.

Also we unplugged it when we made attempts 1-5 on this thing. I assume your concern is inadvertently turning it on? I was wondering if you had another scenario of concern that didn't involve hitting the switch and bad news ensuing.

Allegedly the 1 inch impact is rated a bit north of 1600 ft lbs but with the additional mass of the chuck what is actually being felt by the threads would be considerably less. I'm not sure I follow your scenario correctly.
"If you put an L-shaped piece on the end of the bar you're pushing on and pull on it (instead of pushing down on a straight bar) then, you have the two torques mentioned above working for you. First start with the straight bar and cheater then if necessary, put perpendicular bar on the end of the cheater."
Wouldn't the second perpendicular bar on the end of the cheater bar apply a torque that is then perpendicular to the spindle axis of rotation? Maybe I am not visualizing it correctly.

Steve,
When I was heating it up Saturday we joked about getting liquid nitrogen to pour in the spindle. It's not terribly hard to get if you know someone that stores livestock semen as people do in the Midwest. Dry ice with maybe some oil to increase the heat conduction seems more practical and we won't have to make a million semen jokes.

Phil,

I was using PB Blaster. I prefer Break Away, but PB was handy. I did see somewhere online someone was touting the merits of Kroil in this situation so I may have to get some. May be good for various other things we deal with that have been welded by time.

Anyway I bored the center of clamp-to-be tonight and hopefully Mcmaster Carr shows up tomorrow with some 12point 5/8" bolts and grade 8 nuts. It would be a good Thanksgiving present to get this off.

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Thanks for all the input,

Matt

Matt, one of my uncles told me years ago if you add dry ice and rubbing alcohol that will lower the temperature even more. That is what he used for freeze branding of his beef stock.


I would like to ask a question to all, what can be done in the future to avoid this problem. I have had a few stuck chucks in my career, usually they came loose with a long 2x4 between the jaws but nothing like what I seen on this forum. On the big lathes the chucks were locked on by clamping system, I think a cam lock. It has been to many years to remember for sure.
One would think the designers would have thought this problem through. Bill C.

 

[Tony Wells]

Couple of tips I can remember. Clean all thread and shoulders, make sure everything is the same temperature, and use a little antiseize compound. And don't "snap" it into final position. Push it there with the same basic technique used to remove. Except no impact wrench.