ER collet questions

I'm very probably going to buy an assortment of CAT40 ER32 collets and chucks, as well as some ER16 stuff for when I need to reach into confined areas. The ability to transport coolant is not a concern.

First question: are all of the ER collets interchangeable? Some manufacturers claim wonderous things, but it seems like they all need to be made to a standard, just like R8 or 5C collets. Materials, accuracy, finish seem like they would be a bigger factor than any special design.

Second question: favorite brands? I'm leaning towards a midrange-price unit like Techniks or Parlec. But some people I've talked to are happy with ETM, and of course there is MSC's Accupro, Bison, Enco's imports and Valenite/Collis/etc at the higher end. Bison and Techniks are offered by eBay outfits like shoptoolauctions. Enco has Parlec/ETM on sale, but the Parlec stuff seems to be chucks only, not collets.

Third question: is the chuck or the collet of larger importance for accuracy? Looking at Enco and MSC I can get a wider assortment manufacturers of collet chucks than I can brands of collets.

Midrange chucks and higher-end collets? Spend a little more on chucks and economize on collets? Or just midrange on everything?

Of course, different manufacturers quote accuracy specs at different points, making it very difficult to compare the different brands.

Why isn't there a "Machinist World" magazine that has articles like "Giant ER collet/chuck shootout - 40 major brands go head to head and we tell you who is claiming BS and who is hot!"?

It would sure make these decisions a lot easier.

cheers,
Michael

Michael,
I'm quite sure all er collets are interchangeable. I'm sure you realize though that you can't use a er16 collet in an er 32 holder. They aren't THAT interchangeable.

As for runout, how true are you really looking for? My opinion is as these collets get used day after day, they will develop their wear spots, and corrosion from coolant as time goes on no matter how good of quality you buy. If you spend a lot of money on the ultra precision, how true are they going to run, after about 2-3 year anyway? I know ya don't want cheap stuff either, so I guess I would opt for the midrange stuff all around.

parlec works for me using diamond disintergrating drills at 10k rpm would indicate w/in 3-4 tenths on the tool shank. could tweak a little tighter with a teflon block tapping the high spot. plenty close enough for most work.
davek is right about coolant discoloration (rust) over a period of time...jim

FYI: Boeing surplus had a 100 or so CAT40 tool holders (w/studs) in great shape for $10 each. They also had CAT30,and NMTB50 taper stuff to boot. Too bad I need 40 taper stuff. They also had some CAT40 collet chucks in the contraption to feed coolant down the end mill. No collets or nuts though.

ER collets? Yes on ETM. I have a set of ER-40 in 32nds and they are cleanly made. They are imports as I suspect all ER's are cause I think they are a UK or European origin first in metric now in decimal.

Er's interchangeable? Yes (within each size range), I have tried some supposed "junk" imports to some quality imports and both were well within my specs. I like Centaur, see below. JRouche

http://www.centaurtools.com

Just remember that E-32 and ER-32 aren't interchangable. Some people get them mixed up when selling used, (especially reliable on ebay)so watch for that...
David from jax

look into the nut size....I personally like hex nuts on the tools, I hate those special wrenches... and also the smaller the nut the closer you can get to work holding devices.... I have a few kentametal, a few lyndex, and some Iscar-ETM.... and i cant tell the difference at all....we use mostly er-16 but have some er-32, and we have some double angles as well.....we use endmills as small as .009 with these holders and they seem fine!.......I can remember having to hold a tenth on a millled part, so the runout for me doesnt have to be dead nuts nats but close.....but I imagine tool life would be longer if the tool ran dead on.....good luck....bob

Five stars for ETM, major headache with Bison ER25 collets.

ON an Austrian Emco Maximat 8 lathe, with the Emco collet chuck, the Bison collets were not a good fit to the closer nut, too tight at the front end.

Bought an ETM nut and 2 days later, the same thing, Bison was a poor fit in the nut and would bind early.

Due to a VERY fortunate Travers deal, got a full ETM ER25 set at a fraction of normal price with an oddball shank.

The ETM collets worked perfectly in BOTH chucks which had problems with the Bison fit.

Den

Dave, I was aware that different series of collets wouldn't interchange and was thinking about a straight-shank ER16 that could be held in the ER32 chuck, allowing for a lighter load close-in work.

It sounds like the truer the tools run, the longer the mills last. I'd like to go with no worse than the accepted max runout and better would be nice if I can find someone claiming to deliver it at an affordable price.

Bob, I'll try to find specs on the nut sizes. It had occurred to me to try and find a smaller nut to allow working closer to a vertical surface.

I've gotten some feedback that the Techniks line is pretty nice. It sounds like between Parlec, Techniks and ETM I should be able to find good quality stuff on sale at reasonable prices.

Thanks again.

Michael

Get integral ER16 and ER32 holders. Whatever brand suits your budget. I have a mixture of brands from Ebay and direct from Shop Tool Auctions. They all seem to be about the same but the better ones, ie. more money (Parlec etc.)have hex nuts and ball bearing nut rings.

If you are going to do any small milling or drilling work get a set of ER11 collets and the extension holder that fits in a 5/8"s collet. Be careful with the ER11 holders though,
the cheaper ones are easy to crack at the end where the outside thread and the inside taper come together on the holder.

A good source for you might be U.S. Shop tools. They have ETM, and Parlec, and maybe some other brands. but they also have the holders, and some are in kits so you can save some money buying a full kit. U.S. shop tools seem fairly priced.

I bought some er-16 collets from shoptoolauctions on ebay, said they were "american made" but when they came in, they were new Technic's made in Taiwain. I asked the seller, he said if I didn't like them, send them back. For what I paid for them, I couldn't send them back. They were dropped shipped straight from Technic's, and cost me about $3.69 each. I noticed he started the bidding a little higher ever since then. Technic's quoted me prices about $20.00 or so if I wanted more.
David from jax

How about taking one of these and putting it in something you already have?

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=57026&item=3843744803&rd=1#ebayphotohosting

Seems like a reasonable way to get closer to your work without the expense of the big collet chuck.
David from jax

David: Travers has ER-16 ETMs for $18.10. $20 for Asian collet is crazy

There are big differences in collets once you get beyond the pretty ground surfaces. Somewhere on the Hardinge site is a good story about collet making from selection of the proper steels, heat treating, ageing, grinding, stabilizing.

Asian collets probably omit one or more of the steps which go into a Hardinge collet. That's why you hear stories of them breaking into pieces, poor fit and other PITAs.

Some ER collets are available in what I'll refer to as "native" inch sizes instead of re-labeled metric sizes. For tool holding, this is important for maximum gripping power. I think either Parlec or Schaublin list inch sizes separately.

Den

That is why I stayed with my ebay ones,($3.69each) and didn't buy the $20 ones...
David from jax

David, that is what I'm thinking of getting for the ER16 collets.

The ER32 go smaller than I may ever need - the only big difference on a CAT40 chuck would be a smaller nut size.

But if I need to use a small endmill to reach into something having the chuckable collet holder would move it out away from the body of the CAT ER32 chuck.

cheers,
Michael

Renewing this thread. Tried to mix Techniks ER32 collets with an Iscar ER32 holder and it is way too tight. Had to use a Bison brand collet in the holder, but we will see if it holds as well. Bottom line, I think that even though they are supposed to be somewhat interchangeable, it all depends on how the manufacturer tolerances and datums the part. You only have 1/2 mil tolerance which isn't a whole lot of slop.