ER11M is it completely different?

I didn't think I was a beginner but I may have gone bonkers and reverted to my caterpillar origins. This could be a really stupid question.

I just bought an ER11M nut, on the right, ER11A nut on the left. I cannot get a collet in to the blessed thing. It doesn't seem to have the off centre cut away to hook it in.

Does the ER11M have some clever wrinkle that I am unaware of, or have I been sold a pup?

Robin

Mini (M type) nut should still have the off ctr hole as you can see in this sectional drawing.

The smaller internal thread dia is likely to mean you can't tilt the collet over so far to snap it in

Edited By JasonB on 02/11/2017 16:00:10

So I won't look like a right twit when I complain. A free replacement would be nice.

Maybe I should buy another nut to try out first, just to be sure.

Actually I am quite tempted to buy one nut for each collet in the set, could save vast amounts of faffing about, cursing swearing, stabbing fingers with screwdrivers etc trying to prise the damned things out

+1 Jason. Note from Arc's websight ---

*Note. Mini collet nuts (Type M) have a smaller thread diameter and are not compatible with Type A or Type T1 collet nuts.

Keith.

Push a tube over tail of the collet to compress it and it should be easy to remove/insert.

Robin, as you seem to have bought just a nut were you hoping to replace a standard A type nut with it 'cause that won't work even if you could get youe collet into it, you need a mini chuck.

I did try screwing the nut on over a collet to see if it might close down enough to snap in to place but all the slots closed tight and then it laughed at me

I had the Dickens of a job finding a straight sided collet chuck 12mm round and 180 mm long in the shank. There was not a lot of choice, hence ER11M.

Edited By Robin on 02/11/2017 16:43:59

I had a nut that was very difficult to get onto the collets with arthritic hands. I just put it in the four jaw, centred it up on the eccentric and took a fine skim. No more difficulty inserting or removing collets.

Russell

Hi,

I've just been making a ER20-M type spindle for a nut I purchased from china. It has the eccentric ring for retaining the collet and just like a regular nut but it is a bit more fiddly to get the collet in. The advantage being you have a less bulky nut which would allow access in to smaller spaces and possibly a higher top speed on the spindle which is not important for me.

This is a link to a a copy of a rego fix document that defines all you need to know about ER collets, ER collet spindle cavities and from that you will know the internal dimensions of the nuts (including the M type):

**LINK**

I've not found such a useful document from the rego fix site directly. It should make everything clear.

Steve

I have ER chucks in ER8, ER16, and ER32. One of my ER16 chucks is type M. I never experienced any difficulty getting collets out of the nut. I push the small end of the collet to the side. If it doesn't release I rotate the nut a bit and try again. I keep doing that until I find the "sweet spot" where it releases. It only takes seconds.

I must admit I have no trouble with the ER32's on my big mill and my lathe, but while investigating this problem I dug out an old ER11A nut to see if the new collets would fit that. It went in but it was a pig to get out. Maybe I just need more practice on the smaller sizes