On Tue, 15 May 2012 09:03:51 -0700 (PDT), Stanley Schaefer
wrote:

On May 14, 8:28*pm, "Existential Angst" wrote:
Iffin you REALLY wanted to be sure that a nut won't fall off a screw, or a
screw will loosen, wouldn't plain ole 2-part epoxy be the best bet?

Also, if an epoxied screw/nut did have to come off, wouldn't a little heat
do it?
--
EA

Nylon insert nuts or deformed locking nut will do it, if you ever have
to get it apart. A nut with a check nut will work as well. Could
drill and wire, too. Castle nut with a cotter pin works for car hubs.
If you NEVER have to remove the fastener, just rivet the joint.

Threadlockers are really meant for bolts or studs going into tapped
holes, there are nuts designed for locking duty, see above. Epoxies
really suck at holding shear forces, which is what you get with a nut
unscrewing.

I am not sure how epoxy behaves on threads but in a "shaft-in-a-hole"
application when epoxy fails it is a catastrophic failure and the
shaft then moves quite freely. If one uses a retaining compound
similar to a threadlocker (Loctite 680 or Vibratite equivalent) the
shaft may move if enough force is applied but once the level of force
drops the shaft is stuck in this new position and one needs almost an
equal amount of force to shift it again.

Michael Koblic,
Campbell River, BC