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Re: needle valves / Teflon tape

John wrote:

>Either Tom Barr, or Wright Huntley in a recent post
>warned against using teflon tape on a needle
>valve....Or was it after a needle valve? Why?

It's not a good idea to use Teflon tape *above* (before) the needle valve 
because tape bits can easily plug the valve if they get into the line and 
work their way down.  If you do use tape, it's important to wrap the tape a 
few threads before the end of the fitting -- definitely don't let it hang 
over.  Otherwise, you risk shredding the tape and getting bits into the 
line (it makes it easier to start the thread, too).  As Tom alluded to in 
his post, small fittings are nearly impossible to tape properly as the tape 
is often wider than the threads.

Also, if you remove a taped fitting, you should take care that all the old 
tape is cleaned out of the threads and insides of both the male and female 
fittings before reusing them.  I keep a small wire brush around just for 
that purpose.

Generally, it's best to use pipe dope for gas fittings.  But folks 
shouldn't panic if they have used tape.  I have myself.  Just be aware that 
these problems can occur.
Chuck Huffine
Knoxville, Tennessee