Thread: Collets for a Lathe

Hi Guys and Gals,

Ihave an Al330 Metal Lathe. I have been drooling over collets to improve the runout on holding in the headstock.

I know that Hare & Forbes have a collet chuck and collets that wili just fit the lathe but I'm very thrifty (O.K. a cheapskate). This setup has what they call a 5C Chuck that has a draw bar to lock the collet and the 5MT Chuck in the head stock.

I saw Rod mention that he has bought ER collets and I imagine a Chuck from Hong Kong. I have looked around on the site and saw an ER40 collet set and a 3MT ER Chuck that I think would suit me just fine. 5MT of course would be better i.e. no taper adapter.

Questions.

Are ER Collets only for Mills and the like or are they usable on Lathes?
Is the drawbar needed or is the friction of the Morse taper sufficient?
If not does the ER Collet Chuck have a thread in it which could have a drawbar attached.

Rodm or simo may be the ones to answer but of course any one may contribute. I have kept it in open forum so others may view the responses.

OK people it's over to you. No rod the CNC is still in the same state working but unfinished and dejected. I'll get a round TUIT one day.

Cheers

Hi Brian,
We grow that rount TUIT over here too but we always finish our CNC machines. Consider yourself hassled for this year.


I have the AL330A so I am familiar with you lathe.

To answer your questions as best I can

Are ER Collets only for Mills and the like or are they usable on Lathes?
Collets are used equally on lathes or mills or any machine where you want to grip with more accuracy than a chuck.

Is the drawbar needed or is the friction of the Morse taper sufficient?
Drawbar is definately needed to pull the collet closed and hold it there.

If not does the ER Collet Chuck have a thread in it which could have a drawbar attached.
Collet Chucks have a thread for a drawbar. ER chucks you are looking at have an internal thread and the 5C an external thread - see below.

An opinion.
I would stick with the recommended 5C collet set with this. The reason being you can get round as well as square and hex collets in this range. The drawbar is actually a draw tube to allow long lengths of bar to pass through the headstock the same way as the 3 drawer chuck does. Big advantage is you do not loose the bit that is being held by the collet. You make your part then push the bar forward and start the next one. If you are turning brass or ally then there are savings to be had. I say this is an opinion because I haven't physically seen this setup for the Al330 and are drawing conclusions by looking at the photos.

Here is a link for well priced 5C collets including different holding types but you would have to check transport costs and if the draw thread is OK for what you want. Perhaps buy from H&F the drawtube or maybe make your own.
http://search.stores.ebay.com.au/Dis...347546QQsofpZ0

Chime in Steve or anyone else as I am relatively new to machining metals.

Hello Brian,
I have an AL330a lathe with a 5C collet set. The disadvantage of the 5C collet is that it has a limited grip range-Each collet will only hold the size rod that it is designed for but you can easily turn up a reducing bush and slot it if you dont have the exact size collet.Each ER collet will grip a range of sizes.However as Rodm says ,the 5C collet allows you to hold long lengths of stock because the drawtube has a larger ID than the collet .After being out bid a couple of times on Ebay,I made my own 5MT to 5C adapter (I had access to a cylindrical grinder) and draw tube which had to have a thread cut on both ends. .I had a plastic handwheel which I bushed and threaded. I reckon $200 for the set from H&F is a bargain. I bought a set of collets (used) on Ebay from US which were good value but I think the Chinese ones would be OK. Have fun!
Russell

I would like to join in on the subject of collets, as I know nothing.

I soon will have my Hercus 9" lathe up and running, and no doubt will venture into the world of collets.

The headstock spindle accepts a No. 2 morse taper, and according to Hercus info, I'm going to need a nose adaptor that fits into the headstock, a draw bar, and of course some collets etc.

What do the terms 5C and ER mean, or more to the point, what do I need to suit my Hercus. There is no specific info in the Hercus manual or Text Book of Turning, to say.

I have the torch, just need some batteries.

All help appreciated.

Ken

Ken,

Collet chucks with MT2 tapers are available, I bought this one for my woodworking lathe, it will also work with my yet to be acquired metal lathe.
I bought an ER25 which goes up to 16mm, an ER32 goes up to 19mm. There is also an ER40, can't remember the max size for that.

A set of collets like these will get you going.

There are lots of websites with info on collets, chcuks and ER sizing on the internet. Google will find quite a few.

Great thread Ken!

Here is some info I found on collets

http://en.wikipedia.org/wiki/Collet

http://www.gemcolletsindia.com/er_type-collets.html

http://www.mmsonline.com/articles/050203.html

Grahame

Ken double check your spindle taper before you buy anything,you should find it is no 3 morse.

Big Shed, Grahame, and Pipeclay,

Thank you gentlemen.

OK, I now have some understanding of collets

Pipeclay, I must be losing my marbles, or one too many glasses of "medicine", of course the headstock is MT3, and the "medicine" is Fresh Dry White.

Down to specifics, where do I purchase a nose adaptor and draw bar, specifically for the Hercus, and one that will accept ER collets, and more over, what size ER collets should I look at.

If that's a tall ask, is it down to eBay, or Mick Moyles etc?

Questions, questions, sound more like a school kid, eh Gra?

Regards,

Ken

Both H&F and Carbatec sell chucks and collets, usually in sets, also McJing.

I found that the Ebay seller I eventually purchased from was far cheaper than these sources and he gets very good references on the US pen turning forums.

He also has MT3 chucks.

Size is really up to you the bigger you go, the greater the max size they handle, but conversely the smallest size gets bigger as well.

My ER25 set goes from 1mm to 16mm in 15 steps of 1mm, the range of each collet is 1mm.

Hi,

This is another collet system that I haven't seen mentioned here previously. It is known as a collet chuck that I used quite often at one places I have worked at. They are very good but I wouldn't use them unless the diameter you are to hold has a length at least 3D (D = Diameter). Why, I had a few items "pop out" which isn't recommended unless you are training for a boxing career.

Regards
MH

Big shed,

The mud is beginning to settle, things are getting clearer.

I've looked at some of the leads Gra posted, and looked at the drawings.

Correct me if I'm wrong. The nose adaptor slips into the lathe spindle with it's external thread and chuck sitting out proud.

If for example I choose ER25, which will hold a work piece of say 16mm max, then the work piece can only be a few inches long. In fact, it can only be as long as the collet and chuck allows.

This then means, that a work piece of say 300mm can't be accommodated, because behind the nose adaptor, will be a draw bar preventing this.

Are these reasonable assumptions?

Would still like to know what 5C means.

Ken

Ken,

Not really overly qualified to answer those specific questions as I am (not yet) a metal turner.

My ER25 chuck and collets gets used on the wood lathe, primarily for pen turning, where it holds a pen mandrel with a wooden/acrylic blank. The end of the mandrel is supported by the tail stock, so length is not a problem here. The hole through the chuck is 10mm, so if the drawbar is omitted stock of that size can be passed through.

Don't know what 5C stands for but it appears to be (yet) another chucking system.

Like you, I am learning about all this and find that there is an enormous amount of information on the web. Asking Google the right questions is sometimes the hard part

Ken I dont use collets myself prefer just to use a chuck ,but from what I have read the 5c collets allow for longer work to be held in the collet.
Would be more suited to repetitious maching of parts.
From the previous explanations the 5c collet is held from an external thread on the od of the collet,allowing long lengths of round,square and hex stock to be held.
After looking at the dimensions of the 5c collets i dont think they would be suited to the hercus (they would not fit in spindle).
If you do decide to go with the collet setup Mick Moyles have them to suit in metric or imperial,as well as draw bars occasionally,alternatively you could purchase from the states (to suit southbend) at a rough guess $250 to $350 would get you draw bar nose protector and metric and imperial collets to suit.

http://en.wikipedia.org/wiki/Machine_taper

Half way down the page is a table of the morse tapers.

Hi,

Although collets have there uses I don't believe you can beat using soft jaws or a 3-jaw chuck in a 4-jaw for accuracy. As I have said previously "that a 3-jaw is for boys and a 4-jaw is for men" which is the best advice I was even given pertaining to a lathe.

Cheers
MH