Colchester Student -ER40

Hi Clogs,

Have you a 4-jaw chuck? If so then how about these instructions from HH...

**LINK**

The ER40 has the same internal bore angle as the ER32 and you can buy the spanners and closing nuts from Arc for a few quid.

I've made two ER chucks (ER20 and ER32) for my Myford based upon these instructions.

HTH

Jon

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Ain't the student a cam lock mounting spindle.? D1-3 (maybe wrong)

If so you will have to mount the ER40's chuck to a backplate of that fitting.

Also a possibility is that ER chucks are also supplied in a morse taper fitting. That way you could pop one into your spindle bore. - The only downside to this is that it can accept only short lengths of work.

Edit :- You also say you cannot afford  a better lathe. ........... Why should you wish to.? Students in good condition are a cracking lathe and very, very well regarded. 

Nick

Edited By Nick_G on 03/02/2016 11:47:54

Cloggs

I made a ER40 chuck to mount directly on to my LO spindle

Used an old chuck removed the backing plate which had the holders for the gears in

slimmed it down and mounted a disc of steel

bought a used er40 international 40 taper chuck and cut the back off and mounted this in the steel

It worked well still does but then I bought the burnerd collet chuck system and not used it since

I have both types the key operated and the lever operated and the 12 collets that fit ( up to 1.5"

Hi Clogs

I've mounted 2 chucks on re-machined L0 catch plates for my student. They came from Ebay and at about £20 a go were much cheaper that the premachined L0 backplates from the like of gloster, and the accuracy was already there.... An ER40 will go onto one at some point soon as I've got a couple of spares.

I added an RDG HBM 150mm 3Jaw, which is much more accurate than the original 40 year old Burnered one, the only downside is it jams more easily with Cast Iron dust. If I need more accuracy I use collet chuck (multibore), or the huge 4 jaw.

Cheers,

Mark

On a lathe 6 jaw chucks are best considered relatively light duty devices for holding thin wall tube with minimum distortion. Obviously if all 6 jaws are to contact properly and effectively evenly they need to be very a accurately made so a decent one would be correspondingly expensive. Any uneven wear and one or more jaws will be doing no work. Best off with a good conventional 3 jaw.

My best is a 160 mm Pratt Bernerd precision got probably 15 years back when I picked up a nice SouthBend Heavy 10. Cost me pretty much as much as the lathe, from Rotagrip I think. Its done well but, in retrospect, saving £50 with an import D1-4 backplate wasn't the best move as it seems to have shifted bit over the years and needs to be recut to match my current lathe. Camloc pin extensions aren't even either which is annoying. Being the precision version the jaw tips are narrow which is nice for smaller works but would have been nice to have a second set of internal jaws with wider tips for heavier jobs. Must get the Taylor chuck mounted!

Clive.

I bought one of the backplate mounted ER40 chucks from Arc for my Boxford, which I am quite pleased with.

It allows me to share my VMC collet set I only get 20mm down the spindle but up to the max collet size of 26mm from front face down to spindle bore.

Not sure if you can get bigger than 26mm for an ER40.

The accuracy is as good as you can get from the fit on the backplate that you can get and machine.

You do have the option of getting it set up in your existing 4 jaw chuck, but it takes time, alternatively if you can get your hands on another half decent slim 4 jaw chuck you could leave it permanently set in that

We need to know the model of student. Cam lock or LO ?

Yes, RDG actually do collets up to 30mm

If its cam lock .............

Gloster ER Lathe Chuck Camlock Mount

125mm ER40 collet chuck D1-3 £89.50

If it is a round head Student it will be LO.

Not sure about the later square head ones.

Chris Gunn

Late Students are D1-4

Hi Guy's,

should have thought a bit more....dohhhhhh

my lathe is a square top...machine no...F2/70869 1969'ish.....def not a cam lock......the thread dia for the ring nut holding on the chuck is around 110mm....my 4 jaw chuck dia is a beefy 250mm...the inner head stock spindle is a MT5 fitting........times like this I wish I still had my S7 Myford.....ohhh well.....

great idea on using a small 4 jaw but I think the headstock fitting will rule this out but will look.....was really hoping for a simple fitting and no chance of getting out of kilter with storage knock's.....

perhaps I can find a hollow MT5-ER40 chuck some where ....I'll sacrifice the 30mm stock dia for something a little smaller........

hope this helps Clogs

You can buy a LO backplate and fit a ER collet chuck to that which is what I did on my AUD Boxford

Bob,

It's that's an L0 then where is the locking ring ?

Mines a standard Boxford threaded adaptor but you can by LO backplates and fit a similar ER40 chuck

Hi all ,

the locking ring holds the chuck to the headstock , can't actually put a photo on the forum just yet....must learn..

headstock spindle taper:- small end diameter 66mm x large end 80mm plus a locating woodruff key with a MT5 taper inside the spindle.....

as for the Boxford I guess ur ur adaptor just screws on the spindle......if only. it was that easy....hahaha....

I was hoping for something simple and off the shelf.......oh well......

cheers clogs.......

You just add one of these to the backplate above

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Seems there is from ARC :- **LINK**

Nick