R8 collets vs adaptor with ER-40 COLLETS

Guys,

I was looking for a set of R8 collets for my Millrite mill and found a set of ER-40 spring collets with adapter for R8 The set sells for $100. Would it be better in any way that a set of regular R8 collets?

Thanks, Alex

Reply to
Alex
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========= Spring collets such as ER series are much quicker to change both sizes and tools than the R8 collets. Some people claim better retention and run-out. I never could tell any difference.

As the R8 collets wear people will tend to tighten the draw bar more to get adequate grip. Then you get to buy a new collete AND a new drawbar when the strip it. Even more fun when they break the drawbar off or strip the threads and you can't get it out.

I have bought a lot of stuff from HHIP and am pleased with their service, quality and price.

R8 set

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ER collet chucks
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For mill use you won't need the full set of collets. Mainly the

3/8 and 1/2, possibly 5/8, 3/4 and 1, and if you use use small carbide tooling possibly 1/4. see
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Unka' George [George McDuffee] ============ Merchants have no country. The mere spot they stand on does not constitute so strong an attachment as that from which they draw their gains.

Thomas Jefferson (1743-1826), U.S. president. Letter, 17 March 1814.

Reply to
F. George McDuffee

You need both. The collets are slower to use, but they occupy less vertical room, thus conserving machine depth between the quill and table. You should consider smaller ER chucks, because they also conserve horizontal and vertical clearance, over the ER40. Steve

Reply to
Steve Lusardi

Why the need to overtight? My R8 collets have a key slot engaging a key in the spindle.

Mauro

Reply to
MG

============ Problem wasn't the collet turning in the spindle, but the tool turning in the collet after these wore. Didn't do much for run-out either.

Standard solution is to get a longer wrench rather than replace the worn [out] collet, preferably with a higher quality one.

Ancient Chinese god of machining [Ah Shit] is frequently evoked with this mindset.

Unka' George [George McDuffee] ============ Merchants have no country. The mere spot they stand on does not constitute so strong an attachment as that from which they draw their gains.

Thomas Jefferson (1743-1826), U.S. president. Letter, 17 March 1814.

Reply to
F. George McDuffee

OK well said Unka'

MG

Reply to
MG

Here are some sites I've saved, with ER specs

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WB metalworking projects
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Reply to
Wild Bill

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