ER25 or MT2 Collets

I agree entirely. True some sizes get a lot more action than the others but although it took a couple of years I've used all the collets in an ER32 set now.

As always much depends on what you do; I'm all over the place with tools and haven't regretted buying sets. Lacking a cheap tool in the middle of a job is frustrating and I do metalwork for fun. For the same reason I keep a stock of metals in various shapes and sizes rather than buying only what's needed for a project 'Just In Time'.

Always had a sneaking feeling that chaps who know what they're doing don't buy sets though! Ignorance is bliss.

Dave

I have R8 collets and ER collet chucks. With both systems I had problems with the cutter working out of the collet. Where I can not tolerate cutter movement I use end mill holders where the tool shank is retained by a setscrew on the flat of a Weldon shank.

Most of us are likely to under tighten the collet nuts on ER collets. I believe the recommended torque on the ER32 nut is around 100 ft. lb. The spanner furnished with the ER32 holder is a little over 6" long. Even with a cheater pipe on it the length is only about a foot. That would take an effort of 100 lb. applied at the end of the handle. Ain't gonna happen.

I do prefer ER collet chucks to collets held in the spindle. It is more convenient to access the nut on the chuck vs the drawbar. The drawbar is about the limit of my reach.

Thank you everyone for all your advice - I will chew over it all.

- and Dave - on your basis, as far as milling machine tooling is concerned I am totally blissful !

Thanks all

I bought 1/4" and 1/8" ones as well, it's just less fiddly than closing a collet right down. I find 10mm fine for 3/8" tools though.

Sorry, I made an error in my posting about imperial sizes. I did not get them form Tracy Tools, it was RDG Tools. I've just looked and they don't seem to have the set I bought listed any more.

Maurice

I also ended up buying 1/8” 1/4’ and 3/8” ER32 collets for the convenience. I’ve never had a cutter slip but then I use bearing nuts on my chucks:

**LINK**

I also use a longer 4 prong spanner.

I wouldn’t be without my ER32 tooling and apart from a full set of collets I have three chucks, several collet blocks and a Stevensons Spin Indexer.