ER40 Collets

I would buy a good 3.jaw chuck first. If you later decide that you have a need for collets for small work, ER32 and ER25 are more suited to a 6" lathe. And whatever size you decide upon, make or buy a screw-on collet chuck with 1"-10 threads, not one mounted on a 2MT arbor. The 2MT arbor mounted chuck is only good for parts up to about 2" to 3" long unless you use a steady rest. Whereas the threaded type can handle any length so long as the stock will fit through the spindle.

Also, to make an ER collet chuck of either type and any size, you must be able to cut metric threads. Which probably means that you will have to acquire the gears to do whatever thread you need as they did not originally come with the machine. And if you decide that you must make a collet chuck, at least buy the compression nut. You basically can;t make one for what you can just buy one for.
 
Welcome to the forum. Don't be afraid to ask any question no matter how simple you may think it is. There are a lot of great people on here who will help you out.

X2 on passing on the ER40 collets.

I have only been at this hobby for 3 years and didn't know squat when I started. One of the best things that I did to learn how to use my lathe was to make a norman style QCTP. You only need a lathe and a drill to make one. It will give you lots of practice turning and boring to precise diameters. There is a lot of drilling and taping holes too. And layout. Here is a link to my thread documenting my project. https://www.hobby-machinist.com/threads/norman-style-qctp.79705/ You can of course buy QCTP's but that won't help you learn how to use your lathe. And it can get rather expensive to buy the tool holders. Figure on needing 15 to 20 tool holders.
 
mickri is absolutely correct about the need for more QCTP cutter holders than come with any of the sets. This is primarily true of the #101 or in your case the #001 holder for turning and facing cutters. If you have only the one that comes with the set, every time that a job requires the use of more than one cutter, you will spend as much time changing and setting them up as you would have spent if using the original lantern type holder. Plus, you will lose your depth of cut (DOC) setting and have to reestablish that.
 
Yes, I agree, a 3-jaw first.

I made an ER40 collet chuck for my 12x24" Craftsman lathe. The chuck has been more useful than I imagined, and I recommend that at some point you do the same. I buy collets as I need them - I think there is no point in getting a set, as I likely will not ever use all the sizes. The inexpensive Shars collets are fine for my purposes.

As mentioned, ER32 and ER25 collets are less costly, more plentiful, and maybe better suited than ER40 for your 6" lathe. I find that the larger size of the ER40 is sometimes useful, but probably not worth the higher cost.
 

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The TIR is about 0.005 .0005. I obtained this same result from measurements using several collets and several sizes of drill rod, so I think it is about that. Here is a link to the original thread on the chuck:

www.hobby-machinist.com

Yet another ER40 collet chuck for an Atlas

Just completed an ER40 collet chuck for my Craftsman (Atlas) 12-inch lathe. I followed the excellent drawing by Ronald Crowell, Harold Hall's website, and the many YouTube tutorials. This was a real nice learning experience with a variety of operations... boring a precise diameter, internal...
www.hobby-machinist.com www.hobby-machinist.com
 
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I think you meant 0.0005, that's what your write-up in that thread says. And that's quite remarkable as far as I'm concerned, good job. Thanks for sharing.
 
Yes, sorry, I meant .0005. Thank you.
 
Thanks.

Any tips on where to get a three jaw from? Looks like most not original ones require a back plate that needs to be machined first. Are some better than others?

Making a QCTP looks like a good way to practice my skills, I may look at that project.
 
Cost of chucks is about like cost of anything else. There is generally a direct correspondence between cost and quality. And of course other things (such as quality) being equal, USA made will usually cost more than Chinese. Polish and German made chucks are generally OK but like US and Chinese, you can find cheap ones and good ones and seldom will you find both in the same chuck. One of the drawbacks to buying a plain back chuck and buying and machining a back plate for it (besides the time and trouble) is that they will generally stick out farther from the front of the headstock. And you already don't have a lot of space to play with. I would personally try to find an NOSB Craftsman or Atlas branded 3" or 4" chuck. They are of course scarce but do turn up.
 
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