Mars lathe resto

Hi i will be soon starting the resto / revival of my mars lathe.
I dont think the 3 jaw chuck is original to the machine and needs work.
I will end up cleaning it up but jaws need grinding aswell.
Ive 3D printed a holder for my dremel to do this but....

Do i go through the rebuild or do i just buy a new chuck?

Thanks

I'd say go ahead with cleaning up the one you've got and see how it goes.
Only investment is a small amount of time - worst case it will still be better than it is now and even if you end up deciding its not good enough and buying a new chuck you can still use this one for another project/machine.

Steve

Have a look at this video. It shows a jig which allows you to grind the jaws with the load on them in the same direction as when the chuck is in use. This can help to improve the accuracy of the grind by partly compensating for wear. It will be better at the setting at at which you grind the jaws as mentioned above, but should give some improvement over the whole range.

https://www.youtube.com/watch?v=4OMLAJAYKAw

Frank.

i definitely need to do the jaws.

It hasnt been used apparently for over 40 years.

Has thrust issues also, so i think i need another thrust plate maybe.
Then jaws ground it hopefully it would be a lot better

thanks

took chuck off yesterday and cleaned up a little to see manufacturer markings.

Warren and Brown logo stamped into it.

I think ill clean this up and see how it goes, i like the idea of having the nostalgia and the Australian parts.

In the YouTube video, one of the best methods of jaw grinding I have seen.

Col

yeah, i like that jig.

Just dont think i am skilled enough just yet to make it precise enough.

I have seen other videos using a ring or pipe around the outside and retracting jaws until they hold tight.

Quote:

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Originally Posted by canplaythegame

I have seen other videos using a ring or pipe around the outside and retracting jaws until they hold tight.

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That way you are taking the thrust on the opposite side of the scroll or screw from where it (and most of the wear) occurs during use. This might or might not be a problem, depending the amount of wear on the jaw slides and scroll or screw. The other way sometimes used is to put a narrow ring on the inner end of the jaws inside the chuck, and tighten the jaws onto that, which gets the thrust in the right direction, and grind in as far as the ring. Then remove the ring and grind away the shoulder where the ring was sitting.

Frank.