Unusual Chuck

[caskwith]

A friend of mine recently purchased a lathe which came with several 3 jaw chucks, only one of which actually fitted his lathe. That was fine though since he only needed the one. He offered me the others for the price of postage.

Arrived today and one was as expected a large 3 jaw Elliot, rusty but appears to be in good condition. The other however is a bit odd. From the pictures I hope you can see its a 4" 3 jaw scroll chuck, but each jaw also has an adjusting screw like a 4jaw Ind chuck would have. What would something like this be useful for and how would you set it up?

It needs a really good clean as its full of swarf and the jaws are rather stiff. It has been well used but the jaws look to be in good condition, the scroll is ok as well but very unusual also in that it seems to have a pointed thread rather than the normal square form.
No idea how I am going to take it apart either since the body does not appear to split?

[BaronJ]

Hi Caskwith,

Difficult to see in the pictures, but it looks to be of the "Griptru" ilk.  Each jaw can be adjusted independently so the jaws can be trued up to produce minimum runout.  The plate in the recess at the back probably is removable.  Though when I look at my PB chuck its not obvious that it splits in two.

 

[awemawson]

Never used one, but I thought a 'griptrue' centred as per a normal chuck but the whole shebang was shiftable on the backplate using three screws to jack it about:

http://www.600uk.com/products/machine.asp?id=150

[caskwith]

Yes this has each jaw independently adjustable and reversible. Found a name on the front, Wilson Wilton? Of London USA, need to clean that up better.

I managed to split it in the end, was rather awkward as you had to tap gently on the scroll to start it off and then use a punch from the inside but I got there. Scroll is a bit rough and has some damage, also one of the jaws is missing a tooth which is what caused the scroll damage I think. Not sure how badly the damage will affect things, if it was an ordinary 3 jaw then I probably would have just scrapped it but because of the unusual nature I am going to clean it up, file off the burrs and then re-assemble it and see how it goes, the missing tooth may not cause too much trouble after cleaning. Needless to say I am not going to the trouble of ordering and fitting a backplate until I try it out first.

Stripped the Elliott chuck as well, aside from rust and a few dings on the face it looks brand new, scroll and jaws are in great condition, I reckon it was bumped around a shop for a few years and not cared for but also not actually used on a lathe much. I have ordered a backplate and I am going to fit the body with no scroll or jaws and then take a light skim and file before polishing with Emery. Then I'll strip it again, clean it and lube it, I reckon it will turn out nice, shame I only have one set of jaws.

[caskwith]

A bit of scotchbrite and WD40 and I was able to read the name, made by DE Whiton Machine Co, London Connecticut USA.

[greenie]

Here's something you might find that's very interesting, might take a while to download though.

http://babel.hathitrust.org/cgi/pt?id=chi.087215351;view=1up;seq=12

[caskwith]

Here's something you might find that's very interesting, might take a while to download though.

http://babel.hathitrust.org/cgi/pt?id=chi.087215351;view=1up;seq=12

Ha, that's funny, I found that last night also!