Make a collet closer?

[Steevo]

I would like to have a collet closer and some 3C collets for my Atlas lathe, but the prices that the collet closers are commanding (or at least asking) on eBay are crazy for a threaded tube with a knob on it.

Have others here simply made a collet closer by threading the I.D. of a piece of thin wall DOM tubing and making a spacer/centering sleeve for the back end of the spindle, and using a set-screw handle on it?

 

[Pacer]

I'm not familiar with the Atlas spindle, but would think making up a closer would be along the lines of what I did for my 12x36 Chinese.

The 12x36 - and most lathes - has some size of Morris Taper (MT), the 12x36 is 5MT. I took a 5 to 4 MT reducer/adapter - one of the non-hardened ones and turned it to accept a 5C collet.

In your case, say the spindle is 3MT, you maybe could get a 3 to 2 reducer, finish it to accept the 3C, then as you said, use a piece of DOM tubing and thread it to the size thread for the back of your 3C. I made up a 6" round piece of Al for the handle, with a couple holes to accept a shop made spanner wrench to snug up the collets.

 

[CharlieW]

Most Atlas lathes have a MT-3 spindle that uses an adapter for 3C collets. The down side is that 3C collets are not that cheap or easy to find and max size is 1/2".

I've seen many posts elsewhere on making adapters for ER type collets. The typere are several ways to do it but the most popular is the closer that mounts to a backing plate because you can use the full size of the spindle hole. ER collets are fairly cheap, avaliable in many sizes and easy to find.

I had lathes with a small spindle for many years. Once I got a lathe that could handle 5C collets, I never looked back.

Charlie

 

[Steevo]

Most Atlas lathes have a MT-3 spindle that uses an adapter for 3C collets. The down side is that 3C collets are not that cheap or easy to find and max size is 1/2".

I've seen many posts elsewhere on making adapters for ER type collets. The typere are several ways to do it but the most popular is the closer that mounts to a backing plate because you can use the full size of the spindle hole. ER collets are fairly cheap, avaliable in many sizes and easy to find.

I had lathes with a small spindle for many years. Once I got a lathe that could handle 5C collets, I never looked back.

Charlie

If anyone has a link to an article about making the ER collet adapter like Charlie mentioned, I would appreciate a chance to check it out.

 

[pdentrem]

I made my own collet closer using threaded rod and a tube at the collet end and a another piece at the handle end to fit the spindle. I just have a hole thru the handle end and use a steel rod to tighten/loosen the collets.
The adapter to go from 3c to mt3 is obviously just 2 different tapers but I did not have to make one, as I ended up with 2 of them when finding collets and adapter at the local Superflee market.

There is one on this site and at gadgetbuilder.com I believe.

 

[pdentrem]

http://www.gadgetbuilder.com/ER32Chuck.html

 

[Dutch]

This is a shop-made drawbar for a 10" Atlas lathe for 3C collets. I used it for about 15 years.

The drawbar itself is 1/2" pipe. The white piece is a thrust bearing made from some synthetic material.. about anything would do. Nylon or delrin for example. Even HDPE or LDPE. I had to open the gear cover door and leave it open when I used the 3C drawbar. You could bore out the gear cover and make a long spacer so the handwheel is outside the gear cover. I took the easy way and just opened the gear cover.



The knurled aluminum handle is 2 7/8" diameter and held to the drawbar with setscrews.


The threaded end of the drawbar was done separately and silver soldered onto the 1/2" pipe. Come to think of it the threaded part was silver soldered onto the drawbar and then it was threaded so as to be concentric with the drawbar. The threaded part is the most difficult, if you want to call it that.



I had all South Bend 3C collets because I found them in a used machinery store and snapped them up. They were very inexpensive despite being new-in-box. There's not a lot of industry use for 3C collets.

Where else but ebay?
http://shop.ebay.com/i.html?_from=R..._nkw=3c+collets&_sacat=See-All-Categories

I wouldn't spend the money for South Bend or Hardinge collets. The Chinese are plenty good and very inexpensive.

Discount Machine is Shars on ebay. $9.55 each.
http://cgi.ebay.com/1-16-1-2-3C-ROU...=BI_Tool_Work_Holding&hash=item5194a53c04

If you have a 7x or 9x lathe and have never used collets you're in for a treat. In addition to round you can find hex in 3C and I think square up to a certain size. 3C range from 1/8" to 1/2". I don't know if there are smaller than 1/8".

You can also adapt watch maker collets if you need ittsy bitsy collets.

3AT collets are almost the same dimensionally as 3C, as I recall. From memory I seem to remember the length was the major difference. I would concentrate on 3C unless you can snag a set of 3AT cheap.

$25 for the 3C/3MT collet adaptor. They also have drawbars but why spend $140 when you can make one just as good for next to nothing? It's an easy piece of tooling to make.
http://www.tools4cheap.net/products.php?cat=22

As I recall I hand-filed the pipe OD to smooth it out and insure there was nothing to impede function.