Sources of decent quality ER25 Imperial Collets

Hi, I'm looking to buy a complete set of ER25 imperial collets and would like to be sure that the ones I get have an acceptable degree of runout ( I've read elsewhere on this forum that this should be around 0.01mm ). I've seen some advertised by WARCO and was wondering if anyone has bought these and what they think of them or if anyone knows of an alternate supplier.

Cheers

Anthony

My metric collets came from Warco and they're all good. My Imperial collets came from Arc Euro and they're fine too.

More to the point, if either set of collets had been been duff, I'm confident both suppliers would have put it right.

Dave

Do REALLY need Imperial ER25 collets?

One of the advantages of the ER collet, is thatm being slit from both ends, each collet (Except for the very small ones ) has a range of 1 mm. Thus enables them to grip Metric or Imperial , or in between sizes,.

I have bee using my ER25 collets in this way, to hold millinbg cutters, or work, for probably 30 years or more.

Howard

Arc for me too in ER 32, 25 and 16 they give 0.008mm as max runout which is usually quoted at nominal size by most makers.

Biggest advantage of imperial is an imperial cutter will stay in the collet while you nip up the nut, closing  a metric one down needs 3 hands and usually more effort

Edited By JasonB on 02/05/2023 14:20:56

I have 3/8" and 1/4" collets as well as my full set of metric collets, for the above reasons!

Neil

As Neil and Jason have eluded to, 1/4", 3/8", & 1/2" will probably be all you'll need. Or, you could always go searching for that elusive "third hand".

Wind the Z axis up or down in order that the collet with cutter loosley in place contacts the vice/workpeice and when cutter is in the desired position - tighten.

Robert Butler

Powered Z axis anybody?

Obviously with the machine switched off!! it renders the third hand redundant and damage to dropped cutter eliminated.

Robert Butler.

Edited By Robert Butler on 02/05/2023 17:52:25

I tend to just pull the quill lever down and lock the quill then tighten onto a "loose" tool. Once tightened unlock quill and allow to retract. Saves having to crank the head back up.

Don't like to do that when releasing the tool as it can push the tool out slightly which is not good for it if carbide so the third hand is still needed to stop the tool dropping onto something hard

And the "super precision" ones.

I hve bought from APT also and have never been dissapointed.

 I would be wary of imperial marked collets, it is likely that one marked 1/4", for instance is merely a 6-7mm. If you want to get imperial collets you could try the USA, they still use imperial, but postage could be super high.

Edited By old mart on 02/05/2023 20:37:24

Edited By old mart on 02/05/2023 20:37:50

A reminder: You certainly won't need a 5/16" if you already have a useful 8mm. The difference is a mere 0.0625mm (or two and a half thou in proper imperial inches).

Tim

FWIW - The Imperial collets I have (mostly ARC's, I think) 'hold' at stated size, I mean that the 1/4 is a slide fit on a 1/4" shank in it's relaxed state.and the 1/2, 5/8 (and others) also - they don't fall out when you loosen them. Seem to be genuine Imperial sizes & not metric closest fit.

Weston Tooling supply good quality ER25 collets via their UP range with a stated run out of 0.0005mm , but only in metric I believe.

Raised eyebrow... presumably you check the runout using an interferometer?

Neil

Neil , I merely repeated the company's claims . Suggest any queries or comments you may have should therefore be directed to them . It would be interesting to hear the outcome of such a discussion.

Trevor.

Have re-checked Weston's page on their UP collets , and it should read 0.005mm . Apologies gents for my typographical error.

Trevor.

No one mentions the runout in the collet chuck. I asked Cutwel to tell me what the limits were on their ER chucks and they didnt reply !

Presumably if ones chuck is has about 5um runout, it might be worth just rotating the standard collet relative to the chuck until the runout in the two parts tend to cancel (or nearly cancel) each other out.

Gerry