[cnczane]

I read a recommendation that switching to a "bearing collet nut" would eliminate the worry of over- or under-tightening the standard nut.

I've found some manufactuers, but no discussion of how it works, or how it is used in practice.

One that I looked at had "Lock" and "Unlock" markings, suggesting that it doesn't use threads to secure the collet, but perhaps a cam.

Can someone please light me up here? Thank you.

[deadlykitten]

hy, pls share an image/vendor, for that nut / kindly

[mactec54]

I read a recommendation that switching to a "bearing collet nut" would eliminate the worry of over- or under-tightening the standard nut.

I've found some manufactuers, but no discussion of how it works, or how it is used in practice.

One that I looked at had "Lock" and "Unlock" markings, suggesting that it doesn't use threads to secure the collet, but perhaps a cam.

Can someone please light me up here? Thank you.

Well, it has very little to do with over or under tightening the collet the best collet nuts to get are this one, EMT Brand snip attached, some do have a bearing, but not as good as such, as this solid ring, it helps to get the Collet clamped into the holder with even pressure, prevents the collet from turning in the holder when torquing the nut.

With the use of these ER Nuts, you can use more Torque on the Nut, in general it creates a better seated Collet.

A normal ER collet Nut is a bit like when you do up a nut on a bolt without a washer.

The correct torque should always be used when torquing any type of ER collet.

[ToolHIT]

The Bearing Nut allows you to transfer more torque to your ER Collet so you can get more gripping force. With a Bearing Nut you can get around double the holding power over a standard ER Nut. You would still tighten these nuts to the same Ft/Lbs torque spec of a standard ER Nut but the bearings will give you more holding power (you can still over and under tighten this nut at least on the Bearing Nuts we have seen, it is best to use a torque wrench if possible to meet the torque spec listed). Attached are the specs on the Bearing Nuts.

These Bearing Nuts are great for when you are using an End Mill for more than just finishing. ER Collet Chucks are designed for axial forces so tools like Drills/Reamers are ideal and they give great runout so many people using them with End Mills as well. But they do not handle radial forces well so anything more than light milling and they tend to deflect. The bearing nut gives you the gripping power to handle more radial forces so you can take a heavier cut and still get the runout (still not as heavy as an End Mill Holder, Hydraulic Chuck or Milling Chuck).

If you can't see the image well, here is a link where you can blow it up to see it better:
https://www.toolhit.com/products/nut-ern20b

Hopefully this helps!

Mike

P.s. I love the Peoples Republic of Wisconsin as a location cnczane, that cracked me up!