ER11 collets

I have a set of ER32 collets for the mill and lathe with respective collet chucks. I could do with something smaller and ER11 is readily available at a reasonable price. I can hold a 16mm dia straight shank ER11 chuck in a ER32 collet that mounts in the normal way. Is this a practicably sensible approach or a waste of money?

Thanks Martin

Edited By Martin Shaw 1 on 26/07/2022 23:18:49

I have done it when I use small (and as a result short) drills and milling cutters near a shoulder or the nose of a clamp, that stops the ER32 being useable. Not a lot but a few times.

Martin C

I use a straight shank ER 16 chuck in a ER 32 collet when using small milling cutters, works well.

Thor

Depending on your mill you will loose some head room with a chuck in a chuck. I went with MT and R8 shanked ER16 for when I need a smaller diameter chuck and actually gain head room.

Not sure if you also need the smaller collet on the lathe but assuming you have a backplate mounted ER32 then you would loose the ability to hold long work if using a chuck that is shank mounted.

What is the spindle taper system? I made some ER20-ER11 adapters and they work well, as the router spindle is ER20. I would look at getting what ever fits the mill and find it with a 16mm bore to hold the ER11 chuck. The advantage of making your own is that if done between centres, you will have all the main taper in alignment. Then you can orientate that into the mill, and cut a reference inner hole. Then use that to bore the ER11 inner taper and then cut the ER11 thread concentric to the taper. I have purchased cheapy collets that were junk, so then bought some very good ones that are really great. Mine are sold as being better than 0.005mm tir and they are. On small cutters, it really does make a big difference to how well they work.

Hi Martin, I have a ER11 Collet chuck (Arc Eurotrade) which I've used several times when I've had my ER32 collet chuck fitted onto my lathe with total success, saves changing the the chuck when you have further work to do with the ER32 one, and I've also used it in my mini mill for the same reason, so in my opinion, this was not a waste of money for myself. However, it will reduce your working gap in both lathe and milling machine.

Also by having a smaller nut, you can negotiate around holding down clamps on the milling machine easier when you are using a small short cutter.

Regards Nick.

Edited By Nicholas Farr on 27/07/2022 08:36:55

This all arose because I need to turn down the heads on some M2 screws, I can I suppose just about do that in ER32 collets but it is a tad easier in a smaller one. I take Jason's point about losing spindle length and also head height on the mill which is an R8 SX2.7 so a valid concern.

I am going past APT 's door later today and they have 0.008mm TIR collets at v reasonable prices, a 13 piece ER11 set is £42, a 10 piece ER16 set £32, an R8 collet chuck £17 so nothing is going to break the bank. A set of ER16 would be equally cost effective and also give me alternatives that the ER11 doesn't.

I like Neil's approach but I fear my low skill level will cause more frustration than joy so probably better not started.

I think either approach, 11 or 16, will work but there are more options long term with ER16 so that appears possibly a better choice. I guess any tooling is an investment. Thanks for all the thoughts.

Martin

Useful tip? I have soft soldered cutters, taps and drills into mild steel extensions to get close to obstructions still using my ER 20 collets .Colin

Or use high-strength Loctite - no heat needed except to remove, plenty strong enough.

To round this off, I bought a straight shank chuck and the four smallest ER11 collets for a tad under £30 which doesn't seem excesive to me. Any future requirements can be dealt with then. Thanks for all the help

Martin

Too late, as usual, I've come in from the workshop where Im working my way through my latest project. I had to reduce the diameter of some 3mm screws to fit the design I'm trying to breathing life into. Although I have an ER11 collet chuck and set of collets, I have also produced a number of fixtures for the lathe when I needed to reduce the length of some crews for another (different) project, in various sizes. It also happens to double up for holding a screw t'other way round, so that the head is exposed and and thus can be reduced in diameter. This is the fixture in bits:

Quite simply, it's a piece of BMS turned and threaded at both ends. One end is the thread size for the screw to be machined and the other end is threaded to accept the socket head bolt seen on the left. Insert the victim screw in the large end until the required cut-off length is protruding. Then screw in the shouldered bolt until it nips up on the screw. It acts as a sort of back-stop. Reduce length to the right-hand face of the fixture. Similarly, either insert the subject screw into the small end until it contacts the socket head screw, or slip a nut onto the screw to stop it turning in the fixture. Then reduce the head diameter.

That's the latter method. For scale, the screw is a 3mm pan head.

It's taken much longer to explain how to do it than actually machine all four screws.

John

What you really need is a Lantern Chuck John. its in issue 301!!!  Next Project

Edited By bernard towers on 27/07/2022 21:59:44