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How to Remove a Stuck Chuck -- Tutorial

Clemson

Aluminum
Joined
Feb 15, 2006
Location
Upstate SC
This comes up often enough that I would like to show how I remove stuck chucks. This method did not originate with me. I learned it from the fellow who sold me my lathe. The photos are of my 13 x 40 South Bend. There may be issues with using this method with other machines, but I am sure that folks will chime in with nuances that may be required.

If I have a stuck chuck, first I spray the spindle around the chuck threads with Kroil. The stuff is magic, plain and simple. Then I go to work on the chuck.

This shows a 3-jaw chuck mounted on my lathe:

CLEMSON1.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval002.jpg

I made a block from plywood and a 2x4 to fit the lathe bed under the chuck. This is important to protect the ways. I always use it when changing chucks, stuck or not:

CLEMSON2.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval013.jpg

I use a block under a chuck jaw. This one fits great and is made from a piece of square steel tubing. I keep it under my workbench.

CLEMSON3.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval003.jpg

The covers over the gears have to be opened and removed as necessary to allow access to the rear end of the spindle:

CLEMSON4.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval006.jpg

This wrench is made from a 3/4" piece of aluminum that I bored and split. I then attached it to a piece of 1 1/4" square steel tubing for a handle. Construction details are unimportant. I use a dusting of pine rosin from a Little League pitchers rosin bag (Walmart sporting goods) on the wrench faces where it grips the spindle. It helps to keep the spindle from slipping:

CLEMSON5.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval007.jpg

The wrench is clamped to the spindle outboard of the threads on the smooth portion:

CLEMSON6.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval008.jpg

I sometimes use a 1" bar inside the handle as a cheater, but this is normally enough torque to get the chuck started off:

CLEMSON7.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval010.jpg

Next time you install a chuck, remember to oil the threads first. Never spin it on to install it. Just screw it up snug by hand.

CLEMSON8.jpg

http://img.photobucket.com/albums/v187/Clemson/Lathe/LatheChuckRemoval012.jpg

Clemson
 
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That's great! I can see another project on the horizon......

Thank You for sharing that!! That is really nice that you put together such good pictures for the rest of us.
 
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Thanks Clemson!

That is a great instruction for me and others. Very simple and effective. And your pictures show the necessary details. This is the very kind of things that make this forum so great.

Thanks again for you tip!
 
Nice approach to a sticky problem.

:)

Folks please note that if you have a lever-operated collet
setup on the lathe in question, do NOT clamp to the
portion of the spindle that the collet closer engages
with.

The gear and spindle extension are fixed to the spindle
itself with a very modest woodruff key. It will shear
right in half if the chuck removal torque is put through
the key.

You can see the keyway in the photos above btw.

If using this method, use a puller to remove the closer
adapter first.

Jim
 
Folks please note that if you have a lever-operated collet
setup on the lathe in question, do NOT clamp to the
portion of the spindle that the collet closer engages
with.

Don't own one, still laughing.


Clemson, Nice setup, I can make a slide on wrench for mine, and added it to the someday list. Like someday when get a chuck stuck! =)


Doug S.
 
Next time you install a chuck, remember to oil the threads first. Never spin it on to install it. Just screw it up snug by hand.

Clemson[/QUOTE]


Clemson,
What oil are you using on the threads? Would it be a bad idea to use an anti-seize?
 
The best part of this method is that it puts no strain on the lock pin, which is what most other methods do. Nice demo!
chaz
 
Clemson,
What oil are you using on the threads? Would it be a bad idea to use an anti-seize?


I keep a Plews oiler with ISO 46 oil in it for my gear train. I just squirt a bit of that onto the threads and the flat when I install a chuck. I would NOT use grease of any sort there -- not even "neverseize." Grease attracts chips, and no good can come of having chips in your threads.

Clemson
 
The best part of this method is that it puts no strain on the lock pin, which is what most other methods do. Nice demo!
chaz

Chaz, you are correct. There is no stress on either the pin or the back gear. Changing chucks is the operation most likely to strip teeth from your back gear. Putting the strain on the spindle keeps both the pin and the gear out of the equation entirely.

Clemson
 
"Changing chucks is the operation most likely to strip teeth from your back gear."

Respectfully disagree on that one.

Most likely: engaging or disengaging the back gears while under power is the single
biggest contributor to missing dentition on back gears. And reverse tumbler gears,
while we're at it.

Jim
 
Touche!

You are right, of course, Jim. I should have said "...when the lathe is not under power...."

And, in fact, all of us engage the back gears for routine chuck changes. It is trying to unstick a chuck, when we use back gear indiscriminately, that gets us into problems. That is when the wrench can save you some grief!

Clemson
 
You've got me curious now - clearly the spindle wrench as shown is perfect for the
stubborn chuck - but if I could:

A show of hands, please, who's actually done a set of back gear teeth to death
by removing a chuck using the back gears to lock the spindle?

Jim
 
Jim: I have been using the backgears to lock the spindle when I unscrewed a chuck for years on multiple lathes and have not broke a back gear yet. I do not think it would be a problem unless the chuck was really stuck, you used a long steel lever and sharp blows, or you had an Atlas lathe with zmack gears. Gary P. Hansen
 
Very nice, Clemson.

Regarding a stuck chuck, is this a condition that happens normally to a lathe, or is it something that only occurs when a chuck is installed, overtightened, and then left to sit for a long period?

I mean, can a chuck get stuck on the spindle during ordinary lathe operation? Or if the operator is always careful to mount and oil the chuck properly, will it never become stuck?

Ryan
 
IMO, as long as you're careful you won't get a stuck chuck. "Careful" means making sure there are no chips on the threads, if the chuck seems to be tight when screwing it on you stop and find out why, and you tighten the chuck by hand just enough so it's seated. But I expect there's always a first time.....
 
There are two common ways that threaded chucks get stuck in place on the
spindle threads.

1) interrupted cuts. The pounding that an interrrupted cut causes does a great job
of locking threaded chucks on.

2) running the chuck up to the spindle shoulder, under power. Sometimes accidental,
sometimes deliberate.

Never deliberately run a chuck up to seat it under power.

The accidental version of this, is when running the lathe the operator instant
reverses the spindle, and begins to unscrew the chuck. After uttering that
time-honored phrase, the next thing the operator does is flip the drum switch
back to fowards. That's when the chuck socks home on the spindle, if it
has not already started bouncing along the ways.

:)

Jim
 
I agree with Jim except I can add two more ways for a chuck a to get stuck. 1. chips in the thread, so always make sure there are no chips in the threads. 2. Rust! Always make sure the threads are well oiled. Gary P. Hansen
 
Rust, yes, very bad.

I'm still waiting for that guy who says he stripped some teeth off his back gear
assembly removing a chuck that way. Maybe it's a non-issue?

Jim
 








 
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