On Mon, 13 Mar 2006 15:44:41 +0000, Chris Cowley
wrote:

Oh right. I never knew - I've always used PTFE on compression threads as
lots of sources seem to say it should be used (e.g. various DIY books,
http://www.diydata.com/techniques/pl...ompression.htm
).

I guess I can save myself a few pennies by stopping using it, then!

I always use it:

1. It ensures the thread doesn't seize and the joint can be
tightened/dismantled easily at a later date.

2. It seals the thread. This can prevent a leak should any water find
it's way between the outside of the olive and the main body of the
joint. I agree that in theory a compression joint should be perfectly
machined but in a lot of cases they aren't.

sponix