Chuck won't budge!

[Steve Blackdog]

My supernova2 chuck is stuck like glue on my Nova 1624-42. I haven't taken it off for a few months and now it won't budge.

There is no insert on this chuck as it is threaded for the lathe, so there is nowhere to put a spanner. I've given it a spray of the dreaded WD40 and it made no difference. Yes, the grub screw is undone.

HELP!!

I'm hoping someone will tell me the obvious thing I have forgotten....

All the best

Steve

 

[CHJ]

Clamp a long bar in the jaws across the face of the chuck (at right angles to the spindle axis) give it a sharp clout with a big hammer in an anti-clockwise direction and see if that will break the friction joint.

Once off refit chuck with thin plastic washer (made from milk carton or similar) or just thin card soaked in oil, to prevent the friction seal between the metal faces.

 

[Steve Blackdog]

Thanks, Chas

Can I do any damage to the jaws if I hit the bar quite hard, do you think?

Steve

 

[CHJ]

I doubt it, the steel is good for at least 20 tons per square inch, likewise the fixing screws.

 

[Steve Blackdog]

Thanks, Chas, club hammer it is then!

 

[boysie39]

Steve , a word of warning take careful aim and dont miss the target,
It can be very painful for a long time, :roll: :roll:

 

[Steve Blackdog]

Eugene, it sounds like you are speaking from experience!

Good news, with my new found confidence, I gave it a whack and it came free.

For the record, I clamped my Knock-Out bar in the jaws of the chuck in a 9 o'clock position. I then took a 18" length of oak which I had previously turned to 2", and gave it a single sharp whack. It rotated a quarter turn, but amazingly was still rock solid, then I repositioned the bar to put it horizontal again, and another sharp whack and it swung free.

I guess this is like a lot of brute force questions, you really don't know how much force is too much so you don't give it enough.

Thanks again, folks.

Steve

 

[CHJ]

Sounds like it's a little more than just friction stiction, I would give all he mating collars and faces a quick polish and apply some dry lube or wax before re-mounting.

 

[woodyturner]

I always use Rocol anti-seize compound it is a copper based compound used in engineering just apply a little to the thread and on the back of the chuck every now and again depending on how often you screw and unscrew your chuck and you will never experience that problem again
Rocol lubrications, Leeds,
http://www.rocol.com
http://www.rocol.com/corp/index.php?opt ... Itemid=120