Lever scroll chuck with one hole set

Just got a new pal, Drummond number 2 which was saved from a house clearance not too far from me

Plenty of work to do to get her going again but problem number one was a nice looking original scroll chuck still holding its workpiece from possibly decades ago and not keen on letting go

Suggested solutions to this problem are entertained, I have a large hammer ready to batter the workpiece from side to side

The register part has marks which look like they've used some sort of grippy thing to screw her on too, tsk tsk tsk

Edited By Ady1 on 03/05/2021 00:09:36

Clean all the accessible grime out of the joint and carefully apply PlusGas ‘formula A ‘ dismantling fluid.

Whilst it is seeping-in ... make or buy a C-spanner to fit.

After a couple of days ... thump the spanner with your big hammer.

If that doesn’t work ... part-off that workpiece and drill/bore it until it’s just a tube of shim. [which should relieve the pressure on the jaws] and try again.

MichaelG.

So I put a c spanner into the hole and hit it with a hammer and the chuck goes round and round

and do I whack it with the spanner hanging down on the nearside or the farside?

I've got a scroll chuck somewhere, hopefully they all work the same way

Edited By Ady1 on 03/05/2021 01:32:52

You need a spanner on one of the chuck jaws and a C spanner in the hole. Make sure one is braced against something solid and tap the other one in the correct direction. The should be after applying some sort of penetrating oil as suggested above. Figuring out the correct direction may be tricky unless you can see part of the scroll somewhere.

John

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• If the fluid has done its job ... I would hope that inertia would make it loosen before it spins
• Are the jaw slots numbered ? ... if so, that should help you identify the appropriate rotation.

MichaelG

Is there any utility in removing the chuck from the machine first and then submerging in a bucket of something penetrating?

The turning the stock from the jaws is a very good plan as then it does not matter which way you turn it - you just need to induce some movement in the chuck scroll.

Extreme, desperate measure might be hot caustic soda: not only will it dissolve the aluminium stock, but it will help with internal gumming up.

I found my cowells chuck, looked at the scroll and managed to get a result

Put a block of wood from the lathe bed to beneath the chuck jaw, no violence required

Edited By Ady1 on 03/05/2021 08:23:37

It also occurred to my teeny brain that I should have been using this system for my unimat scroll chuck from the very beginning and ignoring the front chuck body hole

The commonly used "two bar system" plays havoc with my damaged thumbs

duh

Edited By Ady1 on 03/05/2021 08:24:12

Well that was easy !!

I only suggested a C-spanner and a hammer because the holes looked rather shallow and if it was seized then you would risk bruising them with a tommy-bar.

MichaelG.

The C spanner is the best most professional approach

I'm just being impatient, I want my new boy toy up and running sooner rather than later

My Burnerd lever scroll chuck came brand new,and had a round tommy bar in th box,this fits the 3 holes on the periphery