ER32 collet won't take 20mm

[fizzy]

Just went to try my nice new 20mm carbide cutter - damn think won't fit my biggest collet. The collet is marked up as 19 to 20mm. The shank of the cutter is 20.02mm and just won't go!
I will have to buy 20mm R8 now.

 

[Agroshield]

So your thread is rather incorrectly titled, is it not?

Which is lying, the collet or the cutter?

You can buy 20-21 and 21-22 in ER32 from Gloster Tooling.

 

[MattH]

Remove the collect and nut from the R8 tool and place it on a solid surface. Then insert the cutter.

Sometimes when the fit is very close you can close the collect up by pushing it into the taper when trying to insert the cutter.

 

[fizzy]

Remove the collect and nut from the R8 tool and place it on a solid surface. Then insert the cutter.

Sometimes when the fit is very close you can close the collect up by pushing it into the taper when trying to insert the cutter.

Yes that would probably work. Fits fine until you push it into the cap.

 

[mike os]

Get a 21mm collect.. They go to 25mm

 

[Guzrik]

Get a 21mm collect.. They go to 25mm

Oh and I thougth 20 was the max for an er32?
I had a similar issue, I bougth a set with 13 to 12 mm but all 12 mm mills I have are minus a few hundreds so need to buy an 12 to 11mm extra.

 

[mike os]

They go to 25 or26 I think... bit costly but cheaper than larger versions

 

[Guzrik]

Seems different than in Holland then, strange.

 

[Seadog]

20mm is the maximum for ER32 as far as I'm aware.

But they do seem to be available up to 25mm.

 

[Tom O]

I had a none 1/2” collet on my Haas that wouldn’t take a 1/2” endmill until the temperature normalized.

 

[mike os]

Definitely available.. I have some

 

[fizzy]

They go up to 26mm but £20 each

 

[northwest]

They go up to 26mm but £20 each

Good tooling isn't cheap.
I bought a cheap set of oversize collets, gave them away in the end and boughtgood replacements.

 

[Agroshield]

Oh and I thought 20 was the max for an ER32?

It is the maximum standard size and the maximum size you will see in a collet set.

Someone realised that it was possible to extend the holding range by producing so-called oversize collets. I have only ever seen them in ER32 and ER40. Think of them more as a get-you-out-of-trouble device than for regular hard use. Their gripping power is reduced and the collets can be delicate as the nose is very thin.

 

[zx9]

It is the maximum standard size and the maximum size you will see in a collet set.

Someone realised that it was possible to extend the holding range by producing so-called oversize collets. I have only ever seen them in ER32 and ER40. Think of them more as a get-you-out-of-trouble device than for regular hard use. Their gripping power is reduced and the collets can be delicate as the nose is very thin.

Oversize collets were sounding like a good idea, but if they are fragile expecting them to cope with the side loads on a 20+ mm end mill is probably not going to end well.

 

[Brad93]

Just go to a bigger collet holder and buy collets from 20mm upwards

 

[mike os]

Given the tiny differences between 20 and 21mm I wouldn't expect a problem, wouldn't want to go bigger though

 

[Brad93]

Cutwel’s new website even worse than their old one to find anything.
https://www.cutwel.co.uk/20-21mm-er40-standard-precision-er-collet-10-micron-run-out-94
https://www.cutwel.co.uk/20-21mm-er40-standard-precision-er-collet-10-micron-run-out-94

you might wanna buy the chuck elsewhere, 60 day lead on this one.
https://www.cutwel.co.uk/tool-holdi...ks/r8-er40-collet-chuck-cutwel-pro-r8-er40-cc

 

[Shox Dr]

Its a problem when the work piece is at the limit of the collet. If it needs any more than a good push on the bench, the collet is too small. You need to go up a size. Problem then is you are at the other end of the limit for grip.
You can get 0.5mm increment collets (not cheap) that will hold the piece better than the next whole size up.

(I alway tap the end of the workpiece as I’m tightening the collet. Seats better giving better concentricity)

 

[Kram]

I use oversize er40 collets all the time. Once they are tightened up they are fully secure, not fragile and grip perfectly. Just make sure the full length is engaged. For short work put a spare peice in the other end.

Zimi-hk on ebay does not have er32-21 listed, but the er40 27-32 were at my request. If you can wait two weeks for delivery.. they are good quality, worth asking.
www.ebay.co.uk/itm/30-ER40-Spring-Collet-for-CNC-Chuck-Milling-Lathe-ER40-30-30-29-high-quality/293521892431

Other options you can get a spare er32-20 collet an grind it half mm bigger, similar to how chuck jaws are ground. I do have a spare never got around to trying it, and now I have er40 I dont need to. If you want the spare I will pop it in the post. You only need to remove 0.05mm.

Wouldnt buy the 20 quid each collets. That will get you an er40 chuck, then you can go upto 32mm