R8-ER32 Collet question

ddickey

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I hold my brake on my mill when tightening and loosening the ER collet. Is this an acceptable practice or am I putting undue stress on the spindle bearings?
Thanks
 
Opposing wrenches, one holding the spindle adapter and the other turning the nut, is the smart way to do it. Make sure the wrenches are long enough to produce significant torque without straining. Comfortable handles help, too. Torque spec for ER32 collets is 100 ft/lbs.
 
Normally that is how I would do it but no flats.
 
I've been doing that on my Bridgeport with an ER40 adapter as well. Just seemed like what it's for. I do have flats, but a wrench big enough is heavy and expensive. I thought about making a simple one from aluminum plate, might be a fun project.
 
I do have flats, but a wrench big enough is heavy and expensive.

I use slim pump wrenches for my ER-40 & ER-16 collet chucks. I didn't like the idea of using a big heavy wrench. Mine are Proto but they're available from Martin & Armstrong as well.


290815
 
I use a 1/7/16” service wrench, a Wright #1446
 
I don't own er collets but if the spec for tightening a 32 is 100ft lbs. I find it hard to believe it's being done with two 6" wrenches opposed done in one hand. I've been turning wrenches for 25yrs and 100ft lbs on my 18" torque wrench is alittle effort. I would imagine a lot of user are under torquing the nut? Just my 2cents.
 
I would imagine a lot of user are under torquing the nut?
You would be correct, though they seem to mostly get away with it. I am not very savvy on ER collets, but that is the published spec, 100 ft/lbs for ER32 collets. It could also be an accuracy thing. Maybe incorrect torque causes different runout?
 
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