Need help with collets

Recently obtained some end mills for light-duty milling in lathe, but need collets for them. Lathe spindle is 1MT, end mill shanks are 6mm, 8mm, 10mm and 12mm. Can't find individual 1MT collets to suit so probably need to go to ER collets, but what size? ER16 seems suitable for up to 10mm but ER20 will go to 12mm and still available with 1MT shank. Any thoughts??

Hi Geoff,

Harold Hall has a nice description here for a collet chuck which will thread onto the spindle nose of your lathe rather than blocking up your spindle... **LINK**

This method can easily be adapted to make an ER20 collet chuck that will thread on your spindle nose (?) - with the same 8 degree taper which would open up the possibility to use it for holding workpieces too.

Arc Euro sell ER20 collets, nuts and spanners at reasonable prices.

HTH

Jon

Geoff

Some information regarding the spindle nose would help widen the choice, is it threaded, does it have a backplate fitted for chuck mounting. ?

Emgee

Edited By Emgee on 25/10/2016 14:03:21

One of the recent threads regarding ER collets for tool or work holding had the torque figure for correct tightening of ER nuts (or a link to it) as, IIRC, 100ft.lbs. I am surprised that with this in mind there are no spanner flats machined on the collet holder body in the link above to allow use of a large spanner for collet tightening and releasing. I know that some ER32 collet holders are supplied with suitable flats. Maybe it's the ones without flats that cause problems for some people with cutter movement during machining. I would be wary of trying to achieve this sort of torque with a tommy bar in a Ø6 hole or with a pin wrench. Insufficient tightening may lead to the unexpected movement of the milling cutter in the collet.

I know that milling in the lathe is not usually a high force, maximum metal removal rate, operation but any slipping of the cutter is clearly not welcome.

Martin

If the nut uses a C spanner I can't see why a pin or C spanner on the body would not give the same amount of grip

Edited By JasonB on 25/10/2016 16:19:44

I use a 6mm bar and a C-spanner. I know the collet is tight when the bar bends. Next time, I turn the bar round and when its straight, I know the collet is tight

When the bar breaks, it will be time to get a second c-spanner.

Neil

Thanks for the advice. Probably will go to the ER20 as i can get them locally (Brisbane, Australia) at a reasonable price and they have a 1MT mounting which will fit my small lathe spindle. Otherwise i might look at the threaded chuck option, my lathe has a 1inch BSF thread nose to which the chuck backplates etc fit. I have a spare backplate i could make into a ER collet holder.

hi I have a question which i think someone in the forums will know the answer to, I bought a myford lm7 off Ebay a few months back with some tooling which seems to suggest it was used for production, what I need to know is a bunch of collets that was with it the code on the collets is MA99E made by Hardinge it came with a quick release lever but I plan to sell it on ebay as I have no use for it, I need to know is there an adapter that will take these collets and marry up to the ml7. thanks for any info John

I have a Myford/Drumond M Type lathe and use m1 taper to ER20 collet set. It has flats on the body and a C spanner for the collet nut no slipping on the cutter. From RDG Tools.

David

.

Have a look at this advert, John **LINK**

https://www.gumtree.com/p/lathes/myford-lever-collet-chuck-22-ma99e-hardinge-collets-super-7-ml7-ml7r-ml10-etc-/1211231030

That's the arrangement Myford used for the MA99E collets.

... Their other [MT2] collets were very different.

MichaelG.

John,

This thread **LINK** will probably answer your question.

HTH,

Rod

Hi Roderick,

Thanks for your reply sorry I was slow getting back to you, yesterday before I seen your reply I recieved a message back from an ebay trader who is selling lots of this type of collet and to use them on a myford the qick release collet holder has to be used so I will have to sell all the collets with the qick release and buy some of the ER 32 type.

Thanks again. John