Hi John, you might be looking at the wrong nut on the Rego-Fix spec. sheet. Their standard ER40 collet nut suggests 176N for both the plain nut and bearing nut.Thanks for that link. Interesting, their torque spec for ER40 is 128 NM which is 94 LB FT. Lots of other sources specify 130-140 LB FT for ER40. I guess I've been over tightening!