"CW" writes:

Loctite generally causes more problems than it solves. The need is for
getting the fastener tight, not gluing it in a loose position (such as with
loctite).

Fasteners using loctite are not meant to be loose, but tightened to spec.

To get tight and remain that way, the screw is run in until the head
contacts the part to be held and is then turned somewhat further, putting
the screw in tension. Due to the large surface area of the thread
engagement and the 60 degree angle of the threads, they will gal and seize
well before the body of the screw comes under tension.


There is galling and there is GALLING. Torquing a fastener to spec is
putting it under tension and is what holds it and what torque specs
and torque wrenches are for. This causes galling on a microscopic
level whichs is acceptable and does not prevent fasteners from being
torqued to spec multiple times. This is common with many fasteners of
varied materials. Stainless steel IS highly prone to galling, but can
still be torqued to spec without lube and without major galling, but
it's a crap shoot. When SS really galls, you'll know it. That sucker
is welded and will have to be broken to remove.

under proper tension and it will hold much tighter than it would dry. The
lubricant used must be a high pressure type (Lubriplate, Antisieze, etc.).

Good quality lubricants like motor oil, graphite, etc, can
provide adequate lubrication.

Something like 3 in 1 oil will not do it.

Not a great choice, but better than a poke in the eye with a sharp
stick. Also, WD40 is NOT a lubricant.

Putting the body of the screw
under tension is the same way a lock washer works. Though the screw may not
be really tight(due to the galling), the spring pressure of the washer holds
the screw under tension preventing it from loosening.

Lock washers work only partially by tension. The primary
locking mechanism is by the washer digging into and deforming the
fastener/contact points into a nonslip surface.

without the application of Teflon tape or pipe dope before assembly. Pipe
dope and Teflon tape is NOT a sealer. It is a lubricant which enables you to
tighten the threads enough for the threads to make a seal.

You can turn bare pipe threads beyond their max engagement and they
will still leak. You can turn bare pipe threads to optimum
engagement and they won't seal, but upon adding tape/dope and turning
to same level of engagement, sealing occurs. Yes, it is a sealer.
And, yes, it is also a lubricant.

The point? Use some anti seize on the screw.

At the very least, some sort of lubricant is preferred. Even alcohol
is better than nothing. OTOH, using no lubricants whatsoever is
acceptable practice under required conditions, regardless of the
fastener material. Depends on the application.

nb