Stuck 3 jaw chuck

[Willy]

Walter if you'll read my previous post you will see that there are clamps on certain lathes that do indeed have clamps.
They are there to prevent the backplate and chuck from unscrewing under a heavy load in reverse.

[Willy]

I guess no one is buying my theory that the difficulty could be contraction of the chuck due to cold.

The spindle and the chuck/backplate are at the same temperature.
True, if somehow you could heat the chuck/backplate without transferring any heat to the spindle it would help, but that isn't an option, unless you want to take an oxy/acetylene torch to the backplate...not a good idea.

Try my method, I have had very successful results with this procedure on numerous occasions. The way I see it you have nothing to lose. The more you try and fail, the greater the chances of something going wrong and damaging your lathe.

[moe1942]

Maybe we are beating a dead horse. The OP hasn't said if he got the chuck off or not. I could have had it off in less time than it takes to construct this post..

[Walter]

Willy,

Thanks for the heads up. I've never seen that before, but like anything we all learn something new everyday.

[Terry L]

And who suggested doing that???

I did !!! So pardon my ignorance and pass the syrup.

Actually, my chuck wasn't stuck and that's just the way I change my 3 jaw to the 4 jaw. So it really doesn't take THAT much of a "whack" to get it off.

[Arthur.Marks]

Is it off yet?

[panchula]

Temperature differential. I removed the chuck from the back plate, then replaced the socket head cap screws back in the backing plate to provide a leverage point. Next, I locked the spindle with a strap wrench -- back gears are expensive and surprisingly fragile. Heat was applied with a heat gun to the backing plate until it was hot enough for a drop of water to sizzle. A handful of snow was quickly applied to the interior of the spindle (if you don't have snow handy, ice cubes or a can of "dust off" compressed air held upside down would work as well). A three foot length of two by four was inserted between the screws sticking out of the backing plate, and the plate spun off so easily, I did a double take.

[moe1942]

I did !!! So pardon my ignorance and pass the syrup.

Actually, my chuck wasn't stuck and that's just the way I change my 3 jaw to the 4 jaw. So it really doesn't take THAT much of a "whack" to get it off.

Didn't mean to sound critical..Just conjured up a brutal image...

I have inserted chuck key and gave it a quick jerk..many would go on for pages how bad that is/was...

[Terry L]

Hey, no offense taken. It's all good and a lot of fun learning and joking. Who says you can't teach an old dog new tricks ? I have learned a lot from y'all. (And yes, I'm from the deep South.)

[flathead4]

panchula,

I recall a friend of mine had a stuck chuck on his Heavy 10 and ended up doing like you described. Removed the chuck from the back plate and applied heat. As far as I know he did not appy ice but he used a torch to heat it and was probably able to heat the plate faster.

Tom