Dissaembling a Myford/Burnerd 3 jaw chuck

I have a 3 jaw chuck by burnerd with an internal thread. Stamped "made speacially for Myford ML7" on the front. Problem is I can see there is swarf down in the scoll and with the jaws in it gums up about half way to fully closed. Model 30M

However I can see no seams or gaps where the body dussaembles.

There are 3 screws in the back but when I took them out I couldn't notice anything becoming loose.

Anyone know of a manual for these chucks?

Edited By Rainbows on 08/11/2015 14:23:43

If you can, try opening the jaws fully and removing them. Get a thin punch/ screwdriver etc and rotate the scroll whilst "digging" with your chosen implement! With luck you will be able to "wind" the crud to the outside of the scroll and remove it. It may be best to remove the chuck from the lathe and lay it on its back on the bench.

Good luck - it worked for me!

Norman

PS  A good squirt of WD 40 to start will not go amiss.

Edited By NJH on 08/11/2015 15:12:22

It will separate but the parts are a very close fit.

Edited By Rex Hanman on 08/11/2015 21:12:12  Added link

Edited By Rex Hanman on 08/11/2015 21:34:52

So close that they may not come apart going on some of my chucks.

What I usually do is remove the jaws and flick the bits out with a brush and rotate the scroll and flick some more etc. It's usually possible to get all of the bits out that way with the chuck on it's edge.

That white stuff removed in the link is probably lithium grease. If it has been there from new it's probably best left in place or replaced. I've not needed to dismantle my grip trues but going on the link it looks to be relatively easy.

John

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I squinted with all my might and couldn't see or feel a film down the sides. I have a feeling the middle comes out the back to reveal it but I ended up cleaning the scroll from the outside. Jaws don't bind any more so mission accomplished for now.

Hi

I remove the jaws and spray the scroll while rotating it through the slots with CRC, RP7 or whatever brand of penetrating oil I have to hand. Then while continuing to rotate the scroll I use a wet and dry shop vac with a flat nozzle that fits in the jaw slots to suck out the oil and muck that it has loosened, I usually repeat the process a couple of times. the process works well. the scroll will be clean.

Penetrating Oil is not a good lubricant, (Lightly) oil the Scroll before reassembly with a light oil. not too much or it will attract swarf.

Before reinserting the jaws check the scroll for any swarf that has semi welded itself to the scroll. (And the jaws too)

Oh if you do disassemble a chuck if it is in good condition the scroll is an extremely good fit in the body. It must be removed without tilting or it will get stuck. If it does you will need to tap it with a brass drift through the slots to release it. You may damage the fit in the process if you raise any burrs. Take great care.

Regards
John

When I swap the jaws in my 3 jaw chuck I flatten the end of a cotton bud and hold it in the spiral scroll while turning the chuck key. This removes swarf from the whole length of the scroll. I then use a tooth brush to clean each jaw in turn. I don't know what I would do without cotton buds and toothbrushes, but I have found some of the cheap cotton buds can be a bit flimsy so buy a decent brand. I also use chain saw oil on the jaws before refitting.

Doug

Edited By Douglas Johnston on 09/11/2015 10:05:56