Disassemble and then assemble of an Emco Compact 8 three jaw chuck

Hello all, good evening.

My lathe is a Compact 8 one and I want to clean the inside of its three jaw chuck.
Does some of you, Compact 8 owners, have already dismantled the chuck and can tell me how to do it?
Or, alternatively, tell me where to find an exploded view of the chuck, possibly with instructions for disassembly / assembly?

Thanks in advance
Costa days

Hi Dias Costa,

It is a while since I disassembled my 3-jaw, but I can't remember that it gave me any problems. There are 3 Allen screws on the front and a few more at the back, unscrew them and the chuck should come apart at the line indicated by the red arrow. May be I used a rubber mallet the first time, to separate it. There should also be a reference mark on each half (below jaw 3 on mine) to help you assemble it correctly.

I hope this was helpful.

Thor

Edited By Thor on 16/09/2015 06:40:58

Hello Thor, good morning.

Thank you for your help.
Already dismantled Chuck and everything went well thanks to the information you gave me.
I have one more question: what kind of grease you used? Thin, thick, sticky, made with lithium, etc.?

Thanks in adavance
Dias Costa

Only one grease D costa and that is a Graphite paste that will not fling out when rotating,

Clive

Hello Clive, good afternoon.

Thank you for your help.
At the moment I don't have any grease with graphite. But I do have a grease with Molibdenium (Molykot) and another grease with Lithium (BP Energrease). Do you think some of them acceptable for the purpose?

Dias Costa

Edited By dcosta on 16/09/2015 15:32:23

Hi Dias Costa,

Glad to hear you got the chuck sorted, I used a thick "Molykote" grease on my chuck. Like you I didn't have any graphite based grease so I used what I had in my workshop.

Thor

I think you will find in general not a good idea to grease a chuck internals......

They are normally assembled dry so not to attract swarf,thus leading to them jamming up.

Powdered graphite being recommended....iirc....

Dias, use the Molykote grease, it's only white graphite grease anyway. The reason I use Graphite grease is because it's not sloppy and stays in place and seems to coat the parts.

How did you get on finding those plastic trays? Ice stick trays, I have one unopened pack of 2.

Clive

John, when I dismantled my Emco chuck for the first time, there was in fact some grease on internal surfaces, so it seems the factory used grease. I bought the chuck in the nineteen seventies and have only had to dismantle it twice. If I could get dry graphite that would probably be a good choice.

Thor

Hello Clive, John and Thor.

I bought my Emco Compact 7 lathe in 1982 and never opened the chuck since.

Today, after disassembling the chuck I saw that she had grease, in addition to lubrication that I put there in the volute and the jaws, in places I could not reach. So I think the chuck was lubricated at the factory with a black grease.
I found that the bevel gear has teeth slightly marked by use. The other parts of the chuck are in very good condition.
Since I have no graphite grease or dry graphite in the workshop, I used Molykote. I may have abused a little in the volute but, as access to it is easy, I will easily remove the excess grease soon.

To Clive: I couldn't found the stick trays in the supermarket. Thank you for your kind offer. It is a shame that we are so far apart...
I usually put the cutters in a plastic box having compartments after I warp them in kitchen paper towel soaked in oil. Some of them I keep in their original boxes when they have it. The last set of milling cutters I bought from Arceurotrade came in very well made boxes which are perfectly suitable for storage. It's a pity Arceurotrade doesn't sell just the boxes...

Especially for Thor: I made a mistake when I started to mount the chuck that scared me. I screwed too tight the pinion's pins and when I tried to fit the jaws, I could not do it. After correcting the blunder, apparently everything was working well in the chuck.
Today I mounted in the Emco Compact 8, for the first time, a 125mm chuck I bought from Emcomachinetools awhile ago. It's a nice Bison chuck but its size strange appears too strange...
One of these days I'll check its concentricity.

Thank you all for your help
Dias Costa

Dry graphite lubricant is used for locks, not sticky so dirt does not stick to it. Sold by most locksmiths.

Dave

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