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Re: [APD] Re: CO2 tank question -- No Tape on a CGA 320

Tape is neither necessary nor especially useful. It won't
improve the seal and you shouldn't expect it to. The tank
should have CGA 320 fitting on it with male threads and the
regulator should have CGA 320 female fitting. CGA 320
fittings are *not* like standard pipe threads. With
standard pipe threads, the tapered threads provide the seal
and using tape or pipe dough helps ensure that the threads
don't have any small gaps. But the CGA fittings  *do not*
seal at the threads! They seal where the flat faces of the
two fittings meet and that's why you *must* have a fiber or
nylon washer between the two -- to seal the joint where
those to seats meet. In fact, applying tape makes it
possible to bind the threads before the fitings are fully
seated against the washer -- althoguh it would take a lot
of tape to do that.

You can usually get the nylon washers at any supply house
that sells regulators or a welding supply shop, etc. and
they cost about a nickel each. Buy a bunch and use each one
only once -- they squish and deform when you use them.
Well, you can get away with using them more than once, but
if you do, then check the joint for gas leaks after you get
everything set up. Use some soapy water to do this (no
bubbles=no leaks), then wipe the soapy water off when
you're done.

You only have to get the fittings tight enough that they
don't leak -- don't wrench off the valve trying to put 90
pounds of torque on it. An eight inch open-end adjustable
wrench (a crescent wrench for you old-timers) should have
jaws that spread far enough to fit the nut and will provide
you all the leverage you need. Once you torque on the nut
the first time, you'll have a good idea of how much torque
is need. First time, you'll want to check for leaks at all
the connections just to assure yourself that everything is

Also, take a look at the washer the first time you
disassemble the fittings and you'll see why it does the
work of sealing -- and why you really shouldn't use them
more than once ;-)

The right parts and the right tools are the diff between a
task and a pita.

Good luck, good fun,
Scott H. 

> >OK, so I got my JBJ regulator and am about to go out and
> buy the tank. 
> >When I connect the tank to the regulator, am I supposed
> to use any kind of 
> >teflon threading or something? Or do I just screw the
> regulator on. I 
> >understand you should use a wrench to make sure it's a
> tight fit.

The biggest AGA Convention yet has SOLD OUT of rooms at the special discount rate.

Contact hotel directly 703-920-3230 for other roomnight discounts possibly available -- ask for the "leisure rate" of $119 per night.  The generic reservation line may not offer the "leisure rate."

For alternative hotel info see 
The Annual AGA Convention, 2004, November 12-14, hosted by GWAPA.org
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