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Boucher
12-15-2010, 06:46 AM
Most stuck threaded lathe chucks result from the use of the wrong lubricant applied to the threads. Grease is the wrong material to put on the chuck-spindle threads. You want a good anti-seize joint compound such as:http://jetlube.com/jetlube/productdetails.aspx?productId=131

This was developed for the tapered thread used on oil well/water well tool joints. These joints are tightened by the cutting force and will become difficult to unscrew if a slick thread lubricant is used. The threaded lathe chuck is also tightened by the cutting force. Use of a good anti-seize will prevent most of these problems. The better compounds contain copper flakes. Any anti-seize would probably work.

Black_Moons
12-15-2010, 08:17 AM
Whats so great about copper in this application? (Not arguing that its not great, Just wondering why copper)

Dr Stan
12-15-2010, 08:34 AM
Whats so great about copper in this application? (Not arguing that its not great, Just wondering why copper)

I've wondered about the same thing. Some anti-seize compounds use copper, others use graphite. My guess, and this is only a guess, is the copper helps reduce galling.

GKman
12-15-2010, 08:36 AM
Those of us that don't live in Texas don't use oilfield POWER TONGS to install our chucks.:D :D :D

vpt
12-15-2010, 08:48 AM
I keep my threads fairly dry and unlubed. Haven't stuck a chuck yet. Only lube they ever get is the wipe down from the oily rag.

Chip_er
12-15-2010, 08:49 AM
I don't think they had any anti-seize in the early 1900 th. Copper flakes I'm not sure either. But, a stuck chuck on a threaded spindle needs "more power". Last night I did just that. I had no choice but to use "by the recomendation of my old machinest freind" a longer heavy square tube and give it a good pull, but watch your head hard hat required ha ha. The tube I used was 5 feet long. The chuck was 16 inches. I got it loosened on the second pull, know to make something to lift it off the lathe with-out damaging the threads.

My thoughts on stuck chucks is the use of steel back plates on steel spindles. It should be CI back plates.
Just a thought!

Boucher
12-15-2010, 09:24 AM
The first really good tool joint compounds were Lead based. In the oil patch the standard was a product called Jimmy Grey but it was really black. It was impossible to get it out of your clothes if you got it on them. The Jet-Lube Kopr Kote contains both flake copper and graphite that prevent metal to metal contact in the threaded joint. Jet Lube is a really high tech lubricant company. They also make a product like LPS3. They make the best spray lubricant for applications similar to WD40 for corrosion protection….. but it smells so bad that I don’t use it anymore.

These anti-seize compounds were probably oriented toward high temperature applications. I also use the older aluminum based compounds like Permatex.

There are recurring problems of stuck chucks that prompted my posting this.

There is a thread in the Third Hand section that concerns how to remove a stuck chuck. Some of those recommendations are good but some of them are scary. This is a case of an ounce of prevention being better than a pound of cure. I hope the posting is helpful to some.

moe1942
12-15-2010, 09:42 AM
Copper impregnated anti-sieze is good for high temp applications. I use a dab of KOPR-KOTE on my spark plugs.

I have never used anything but 30wt oil sparingly on my spindle threads.. The best thing to do is clean threads and register well. Stone any dings or burrs.

If you use anti-sieze I would do it very sparingly. It is a very dense, high viscosity substance. The very lightest film should be used betweeen the spindle and chuck where they mate..

There are very good ways to start a stuborn chuch to give up, None of which I will divulge here. I choose to deny the safety police an opportunity to shake their fingers..:)

The above suggestions are only my opinion based on 35 yrs experience. Your situation might vary.

AllThumbz
12-15-2010, 10:10 AM
There is a thread in the Third Hand section that concerns how to remove a stuck chuck. Some of those recommendations are good but some of them are scary. This is a case of an ounce of prevention being better than a pound of cure. I hope the posting is helpful to some.


Here are some tips for preventing a chuck from getting stuck from my site, and I also have two suggestions for removing a stuck chuck there (see link below). I don't want to break any rules by posting the links, so I will simply repost it here:

---How to Prevent a Chuck from Sticking
Don't spin the chuck home. Rotate it softly into position, then use a piece of wood or metal to torque it home. You don't want it tightening under load, since that can change part location during a cut. Always use a spindle protector when the chuck isn't in use. My lube chart says to use type A oil on the threads same as used in the spindle bearing. Use an old toothbrush to clean the internal threads on the chuck and if it doesn't screw on easily, take it off and clean and lube both threads.


You can also use one of those U-shaped thread cleaners to get those little chips out of the check threads. You can make a nice thread cleaner out of a piece of coat hanger wire or welding rod. It doesn't need to be very springy. Just make a couple inch and a half loops, bend the ends out and file them to a V.


One precautionary tip when mounting the chuck is to place a wooden dowel a similar size to the spindle bore in the jaws of the chuck, extending it into the spindle bore. A 3/4 dowel will work in many cases. When removing the chuck, it cannot fall away from the spindle, it will be supported by the wooden dowel. It also gives you a good handle on both sides of the chuck. You're less likely to drop the chuck on the bed or worse your foot. When installing the chuck this makes the threads almost self aligning. It makes it easy to start the threads, so you can gently thread the chuck onto the spindle. This dowel is universal, it works with all chucks.

Lube the spindle with light oil, more to prevent rust than anything. Make sure you always have a board on the ways when you change chucks as well as a fitted piece of 2x3 to support the chuck until it's fully tightened.

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becksmachine
12-15-2010, 05:25 PM
Stuck chuck??

Just get that kid in the video to hang on to the chuck key and turn it on!

:D

Dave

KiddZimaHater
12-15-2010, 09:44 PM
I apply a few drops of way lube (Vac 2) to my spindle threads everytime I screw-on the chuck.