On Wed, 08 Jul 2009 02:00:54 GMT, (Doug Miller)
wrote:

In article , "Upscale" wrote:
I've just picked up a new portable compressor, hose and an array of fittings
~ all connections will be brass to brass. Do I need plumber's tape for these
fittings or should I be fine with just the brass to brass? I was wondering
what others have done?

Well, you need *some* kind of pipe dope in there, if you think you'll ever
want to take the joint apart a few years down the road. Some folks will tell
you never to use teflon tape with compressed air, but I've never had a
problem. Just make sure you apply the tape to the male threads only, and keep
it on the threads -- don't get any into the air passages.


I use teflon tape, double wrapped in a clockwise direction and do not
cover the entry thread. Carefully used, the tape will take up the
slop in the threads and provide a better seal, while not allowing the
metal to metal joint to seize.

I don't have my Machinery's Handbook in front of me but, if you refer
to it, you will find that there are a number of interference fit
thread engagement tolerances and what we too often get in offshore
fittings is a slop tolerance that is really more than it should be.

Pipe dope comes in flavors (caustic, pneumatic, hydraulic, etc) and I
think there is more chance for contamination because the wet surface
can attract gunk in what is often a dusty environment - and because
I'm more capable of keeping the entry thread clean with the tape.


Regards,

Tom Watson
http://home.comcast.net/~tjwatson1/