How do I keep the chuck from sticking to the spindle next time?

Randy M

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I tried to remove the chuck (3 jaw) from my Unimat 3, but it wouldn't come loose. I finally used an allen wrench in the chuck, another in the hole in the spindle, and a plastic hammer. I came loose on the 4th blow. The allen wrench in the spindle now has a nice bend, but it was cheap one so I'm not upset. Before I put anything back together, I'd like to know if someone has a secret formula (or some widely known machinists trick) for keeping the chuck from getting stuck next time? There are no signs of any rust or corrosion nastiness, but not much in the way of oil or grease either.

Thanks for any and all help.
 
I use a small washer made from a brown paper grocery bag. It goes on between the mating surfaces of the chuck and spindle register -- works great for me. The chuck can still get on there pretty good if you're doing something like interrupted cuts, but the paper gasket really seems to make it less so.

-frank
 
I don't know your lathe, but if you have a threaded spindle which I think it sounds like.
keep your threads clean.
Tighten your chuck as much as you can. Why: a chuck that spins on , on it's own hammers itself on, so putting it on tight prevents it from hammering itself. If you are slightly loose, you run the risk.
 
Put it tight when you install it.

Sounds silly but...

If you just turn it until it stops it may not fully seat then first cut the interaction of cutting will tighten it up.

From od manuals...

Turn chuck gently until it stops.

Unscrew it about 1/4 turn.

Shift back gear in, leaving spindle not I. Back gear thus locking spindle.

Turn chuck rapidly by hand to cause it to seat when it stops.

Take out of back gear.

Also, do NOT use back gear to lock for removing chuck.

Sent from my SM-G781V using Tapatalk
 
I use a piece of parchment paper cut into a washer shape between my chuck and spindle. Wax paper also works here. Also, never spin on a dirty chuck - keep it meticulously clean.
 
I would avoid the use of grease to keep the chuck from sticking. It will turn into a swarf magnet if you do.
 
I use a piece of parchment paper cut into a washer shape between my chuck and spindle. Wax paper also works here. Also, never spin on a dirty chuck - keep it meticulously clean.
That or brown (grocery sack) paper sounds interesting. As far as meticulously clean, it brings up a memory of a rig for cleaning the internal threads. Sort of like a bobby pin with the tips turned out. From 1890s, that's been a point for a while.

What I have been obsessed with is a light coat of nickle based anti sieze. I use it on every fastener of import, including the lug nuts on a 4X4. The torque for lug nuts is much higher for "greased" studs. It must be carefully adhered to. And yes, I have had a wheel come loose, didn't lose it but it did come loose. Worked a double and was too tired to fix a flat myself. . . That was many years back, but I remember.

I use "Nickleze", a brand name. I assume a copper based would do as well. I swiped half a can from the mill for of the high temperature rating. That half can has lasted several years, it doesn't take much. Both lathes have threaded spindles and I change chucks regularly for whatever I'm doing, so probably don't need it. But it;s as much out of habit as concern for the machines. Negative comments welcome, the previous post being the first.

.
 
I'm not sure how it would work on the coarse threads of a chuck mount, but for anti-seize compound on
hand drills, or my bicycle components, a bit of plumber's teflon (PTFE) tape works well. The stuff cold flows, so
it'll take up any empty space at thread crests, and prevents moisture or dirt entry, but at
the takeapart time it ensures that no large metal/metal contact in the threads causes adhesion.

The forces on the threads cause spring-like spreading of the female threaded part, so the available
volume includes non-position-determining space. It ought never result in a canted fit.
 
Both my South Bend lathes have threaded spindles. I blow/wipe both spindle and chuck clean and give it a shot of way oil before installation. Works well for me even if the chuck remains on for an extended period of time.

Ted
 
What I have been obsessed with is a light coat of nickle based anti sieze. I use it on every fastener of import, including the lug nuts on a 4X4.

That's not a good idea. The lug nuts require the friction to stay put. I once made the mistake of oiling the adjusters of my front wheel drum brakes (even though the manual said NOT to do this, but hey, what did they know?), because it made them easier to adjust. One hard brake and both of my front adjusters unadjusted! I managed to limp home and immediately cleaned all the lube off the adjusters and learned a huge lesson!
 
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