MC900 stuck scroll chuck

[petersemple]

Need some idea please.

I have an MC900 lathe, and the scroll chuck is jammed on tight. I have sprayed with WD40, and wedged a long screwdriver into the jaws. With a bang that will turn, but the chuck is turning on the adapter, not coming off the lathe :-( I have put a pipe wrench (only think i had big enough) onto the insert screw and banged again. This time nothing moves but the flat spanned that comes with the lathe to hold the spindle just bends and collapses :-( I guess the thing I really need is a better way to stop the spindle from turning so I can apply appropriate force to the insert and hopefully get it off. Any ideas?

[Optimark]

Thinking out loud here.

Maybe if you remove the chuck, then, if it is possible, clamp the spindle shaft somewhere inside the head stock unit with a pair of vice grips, then use something larger like a stilson to grip the chuck insert and unwind it.

We have one of those lathes at my Men's Shed, I'll have a look tomorrow if I remember.

Mick.

[Colin62]

Does the chuck insert not have flats to put a spanner on it? I’ve only got Nova chucks with inserts on and they have flats for a 38mm spanner which is what I use to take the chuck off, but I’ve got the benefit of a spindle lock.

Before putting a pair of vice grips on the spindle, I’d try lashing some nylon cord around the V belt. Basically wind some nylon cord around the V belt between the two pulleys, pulling the belt as tight as possible on the pulleys and that will hold the spindle fairly tight - hopefully tight enough. I’m not sure if I’ve explained that well enough but can’t really think how to describe it any better.

[petersemple]

Thank you all. It's off! I removed the chuck from the adapter, which gave me better access. I then used the cord around the V-belt trick and that stopped the spindle well enough that a few quick blows on the wrench that fit on the adapter got it off. Next step is to make a plastic washer to prevent it happening again hopefully. I also have an old Sidchrome spanner that came with the house that could be modified with a grinder a bit to work as a sturdier spindle spanner if I need it. Thank you so much.

[Fumbler]

On a side note, maybe a quick rub with copper coat on the thread and wall of the adapter. But if it does stick again, apply a small amount of heat, it does wonders to budge parts.