Chuck removal

[Garno]

Hi,

For the last 2 days I have been trying to remove a chuck from the lathe, it has reached the stage where I no longer know if I am tightening it or loosening it. The lever bar that goes into the hole of the lathe next to the chuck has now snapped, actually it bent and then snapped and the hole itself is now becoming oval shaped.

I have hit the bar with a mallet to no effect and I am now doubting myself as to if I am turning it the correct way. So looking at the job on the lathe square on I have the bowl, screw chuck, headstock, turning wheel. Do I need to be turning the bowl/chuck clockwise with the turning wheel anti-clockwise? or do I need to be turning the bowl/chuck anti-clockwise and the turning wheel clockwise? The bowl is incidental and only mentioned as it is on the chuck and I wont be able to get it off until I free up the chuck.

 

[Dalboy]

Gary have you got a picture of the chuck in place. I can't see that having a bowl still in the chuck will stop you removing the chuck. The hole is it part of the lathe or an insert in the back of the chuck so that you can remove it. What lathe do you have.
All chucks that I have come across turn anticlockwise to release them look from the tailstock end

 

[Duncan A]

Surely the bar is to lock the spindle and hitting it will achieve nothing.
If that is the case you need to insert the bar to lock the spindle and then turn the chuck anticlockwise (looking from tailstock end onto the chuck).
If the chuck is overtightened on the spindle, use the bowl as a lever or find a way to remove a bowl and carefully use a bar between the jaws of the chuck.
I have assumed this is a conventional scroll chuck.
Duncan

 

[Garno]

Gary have you got a picture of the chuck in place. I can't see that having a bowl still in the chuck will stop you removing the chuck. The hole is it part of the lathe or an insert in the back of the chuck so that you can remove it. What lathe do you have.
All chucks that I have come across turn anticlockwise to release them look from the tailstock end

Thanks @Dalboy & @Duncan A I have managed to free the little Bu**er, I put an allen key into the locking hole, jammed a 32mm spanner to stop the chuck turning and wacked the heck out of the allen key. That loosened it.

 

[flh801978]

In future put the Allen key against the bed and use the spanner to undo the chuck pulling the spanner towards you when stood at the front of the lathe
Also a washer cut out of a milk container works well to stop the pair locking up so tight
Ian

 

[Inspector]

You should have put the bar in the spindle hole and turned them towards yourself until the bar touched the lathe bed. Then with a wrench on the flat of the faceplate pulled the wrench towards yourself. If it didn't come loose then tap the wrench with a mallet or hammer and it would break free. Your beating things the assbjckwards way potentially causes more damage to your bearings. If the wrench is too wide grinding the sides until it fits and keep it for chuck removal. Wrenches are cheap enough at the big box stores.

Pete

 

[MARK.B.]

Did you get it sorted Garno ?

 

[Garno]

You should have put the bar in the spindle hole and turned them towards yourself until the bar touched the lathe bed. Then with a wrench on the flat of the faceplate pulled the wrench towards yourself. If it didn't come loose then tap the wrench with a mallet or hammer and it would break free. Your beating things the assbjckwards way potentially causes more damage to your bearings. If the wrench is too wide grinding the sides until it fits and keep it for chuck removal. Wrenches are cheap enough at the big box stores.

Pete

I tried with the bar and turned the bowl towards me but the end broke off. I will make another out of a HDPE rod that I ordered last night.

 

[Garno]

Did you get it sorted Garno ?

Yes, it was a right old job.
I have sprayed it with some PTFE and will make a washer as @flh801978 suggested.

 

[MARK.B.]

Yep i remember him telling my mate Bob about the washer when we went to his place to pick up a couple of graduate bowl lathestop bloke and his man cave is quite impressive

 

[Illy]

Yes, it was a right old job.
I have sprayed it with some PTFE and will make a washer as @flh801978 suggested.

My Dad fit a washer for this reason and it introduced a noticeable wobble, so check it's still running true after fitting.

 

[Dalboy]

Never had to use any form of washer to aid chuck or any other attachment removal. Keep the mating surfaces clean and the threads as well on both the spindle and in the chuck. Always make sure the chuck is tightened up to the surfaces as any slack will soon be taken up when you start turning this will cause the chuck to screw on harder than is needed and make it difficult to remove.
Remove the chuck frequently also helps as well as lets you do the cleaning. I don't think I have ever had any problems with a stuck chuck by following these little rules of mine.
Introducing any form of soft washer can cause run-out as Illy pointed out

 

[Phil Pascoe]

The last time I used mine without a washer I bent a 10mm bar getting it off. Perfectly clean spindle and perfectly clean chuck thread.

 

[AdrianUK]

This washer issue comes up often with turners, some swear put helps, others that it causes problems.
As Dalboy says, if the chuck is not tightened, a tiny amount of slack often results in it becoming very tight once lathe is on, so I now always cinch up tight by hand.
That said, in the past I’ve used a thin washer as described without any issues.

 

[Democritus]

I have used mm thick cork sheets to make washers, but recently have stopped using them with no subsequent ‘sticking’ problems.
D

 

[Phil Pascoe]

If you cut a a washer from waste plastic just be careful where you cut it from - on some containers (like milk) the plastic varies in thickness across the carton. I cut mine from Dettol bottles - the flat fronts and backs are thicker, perfectly uniform and harder so they don't distort.

 

[Garno]

I'm a little concerned about the potential wobble issue it may cause, but I am more concerned about the difficulty in unscrewing the screw chuck in case I damage the lathe trying to get it off.

We now have an empty plastic milk bottle (Mrs G is wondering how it emptied so fast) so I will make one tomorrow and give it a try on a faceplate that has stuck in the past.

The HDPE rod may take up to Thursday for it to be delivered so I will be without a leverage bar until then, I hope it will be strong enough.

 

[Garno]

If you cut a a washer from waste plastic just be careful where you cut it from - on some containers (like milk) the plastic varies in thickness across the carton. I cut mine from Dettol bottles - the flat fronts and backs are thicker, perfectly uniform and harder so they don't distort.

Could I use an ordinary washer?

 

[Inspector]

Use a piece of wood for the knockout bar knob replacement. It can be epoxied on where the HDPE is pretty much impossible to glue.

Pete

 

[Jacob]

C (or "hook") spanner for the holes in the spindle, long enough to touch the bed c spanner - Google Search You'd expect one to come with the machine - maybe the supplier can supply one? Wants to be made to measure not adjustable - just a bit more solid.
Close fitting flat spanner for the chuck - firmer than an adjustable when you tap it with a hammer.
And a washer.
PS you hit the spanner on the chuck. not the one in the holes on the spindle