On Sun, 24 Aug 2008 21:01:04 -0700 (PDT), dpilot
wrote:

On Aug 13, 8:53 pm, John wrote:
mhorowit wrote:
how low do you let your acetylene tank get before getting a refill? -
Mike

As long as you have check valves in the lines, to the point where there
is not enough pressure to sustain the 3-5 psi regulator setting at the
flow demand of the torch.

Acetylene is only unstable if in the gaseous state ABOVE 15 psi.

John

Paul Mee, the lead welder for Aeronca (sp) says never weld with less
than 100 pounds
if you want a good weld.
He said you ain't got enough heat. with less than 100 pounds.
I suppose if you just wanted to heat up something to bend it or
whatever, any psi would be ok
JimV.

what may cause the low pressure limitation is the way acetylene is
stored in the tanks. I am told that it is in solution with some
solvent - acetone I think - and that it is not just a gas as in the
case of oxygen or argon. more like a soda pop with gas disolved in the
fluid to make it stable/non explosive in the bottle.
take the pressure down too far and you may not be getting acetylene as
the gas.

ask your distributor for the details though. this was related to me
second hand.(the guy was getting stuck into me in a model engineers
meeting)

Stealth Pilot

(paul mee is in the USA isnt he? shouldnt that be $200 or did you mean
psi :-) )