I am setting up my first torch in my garage. I purchased a smith
acetylene air torch. The design has been changed in the past
year–there are two gauges on the regulator–the instructions that
come with the torch do not explain them- or give a specific working
pressure. When I attempted to pressurize the torch and check for
leaks—the gauge which shows working pressure (on the left) does not
move from 0. The one on the right does move. The directions say to
turn regulator adjusting knob to the right about 2 turns past initial
spring contact to obtain working pressure. It is not clear to me,
when I’m contacting a spring. Anyway, however it is adjusted, we
don’t get a read.
Also despite tightening the connection from regulator to acetylene
tank, we still get a leak. My husband thinks teflon tape is
frequently used for this. Do you deal with leaks in that way? Any
ideas on why the pressure doesn’t show a reading.
Anybody have some advice. I am planning on returning the torch at
this point and my acetylene tank is off.
Do not use teflon tape on gas fittings also try turning the
adjustment screw a few more turns it may take more than two. If the
acetylene regulator is leaking you may have nicked the threads check
the threads to see if they are nicked any where. The fittings are
brass and easily dented and nicked. Check out smiths website for
gauge pressure. I used acetylene for a very short time it is a dirty
gas and is also very hot. I think if you are just starting out you
may want to try propane it is a little easier to manage and you do
not have little black soot floaters flying around your studio. You
can also get a plumber to hook up natural gas if you have it at your
house or studio.
Also despite tightening the connection from regulator to acetylene
tank, we still get a leak. My husband thinks teflon tape is
frequently used for this.
This is a common misconception. Teflon tape, as any hydraulics
mechanic with training will tell you, is used to keep two threaded
metal pieces (especially, but not exclusively, dissimilar metals)
from corroding or rusting tight, not to seal them. Teflon tape does
very little to seal threaded fixtures (whether hydraulic or gas -
threads are threads) and is definitely not recommended for gas lines
of any kind, since tiny pieces may break off and clog your torch. If
you can’t get a tight enough connection without leaks, the connector
or tank fitting is defective.
First, make sure your regulator is screwed into the tank fitting
very tightly. Then, make sure your torch hoses are also tight. Very
tight. Then, screw the regulator adjuster counterclockwise until it
turns very easily. If you unscrew it completely, don’t worry; just
screw it back in a couple of turns right away. Next, open the knob on
the top of the gas tank all the way. Make sure your torch knobs are
closed, then screw the regulator adjuster clockwise until the gauge
on the left side begins to show pressure. This should start to happen
just after you feel resistance from the spring inside the adjuster
mechanism. If you don’t see the needle rise at this point, close the
knob on the top of the tank, open the knob on the torch and send the
defective regulator back for replacement or repair.
This is the kind of thing I was talking about the other
day…something that will stop me in my tracks. I have taken two
8-week courses…both with acetylene air. I’m still not confident
that I can set-up and use a torch…this is what is holding me back.
I read the other post about the man who lost his life changing out a
tank in an acetylene/air system. I thought acetylene/air was one of
the safer systems. I don’t want to spend another 500 dollars taking
an additional class. I would much rather buy inventory and a proper
torch set-up…but now I’m scared again. Everything else is ready to
go, it’s just this one fear I have to get rid of.
First of all I don’t use Teflon tape on the connections from the
regulators to the tanks on my gas or oxygen. I do sometimes use it on
the hose connections to the regulator, but not that often.
You may not be screwing in the adjusting knob far enough. To test
and to be safe, try this.
Open the torch so gas would flow if there was gas in the hose. Then
screw in the adjusting knob slowly. If you hear or smell gas and the
gauge fails to indicate pressure you have a faulty gauge. If the
gauge indicatesand yo smell or hear gas you just didn’t screw in the
adjusting knob far enough. If nothing happens most likely the gauge’s
diaphragm is not functioning, new regulators can be damaged by
opening the tank valve too quickly, especially on high pressure
tanks(oxygen, hydrogen), so always open tank valves very slowly.
Check the torch by just trying to blow through it, disconnect from
the hose at the handle, then open the valve all the way and see if
you can hear air leak through when you into the handle, blow hard and
listen carefully.
Don’t worry Smith makes good products.
For the leak between the tank and regulator, try tightening the nut
until you hear a squeak. New students have this problem all the time.
If everything that James said does not stop the leak take them in and
get them refurbished they will replace all the bad parts and they
will be as good as new. I did this with my regulators and my smith
little torch and they are as good as new. Much cheaper than buying
new ones.
I would much rather buy inventory and a proper torch set-up....but
now I'm scared again.
I’d suggest you get a small disposable tank setup. Rio Grande has a
decent looking setup for about $180. The bottles are so small, the
potential risk is minimal. If you’re powering a Little Torch you
should be able to solder most jewelry sized items. A #7 tip puts out
plenty of heat for silver up to a couple ounces.
Then, as you become confident with the equipment and procedures you
can think about upgrading. It depends on the volume and weight of
what you’re doing.
I learned on an acetylene air setup nearly 30 years ago. It was
tough going. In retrospect, acetylene is a dirty burning gas that
just complicated the process of learning. Its only advantage is that
its cheap… Well, scratch that, I just looked in the catalog and
its $70 more than the disposable setup.
If you’re worried about leaking gas its simple…the propane has an
odorant added to it so you can smell when there’s a leak. For
overnite just unscrew the bottle from the regulator. And if you want
extra safety you can buy a propane detector from an RV supplier,
about $50.
I’ve read differing ideas on torches here, its no wonder you’re
concerned. But if you’re starting out, as I guess you are, start
small, get bigger, better equipment as the need arises.
Old acetylene is very dangerous. I have used propane for years. just
make sure you proof the connections! let some air into the closed
torch, you will notice the pressure increase, watch for a decrease.
if pressure decreases tighten that connection. repeat for the other
line. also a weak soap solution on the threads will bubble if there
is a leak.
What do you mean? How old is old? What is the danger?
I have an Acetylene B tank (Smith Acetylene/Air torch) which I got
in June '04 and I haven’t used it all that much. It is still quite
full. (I am one of those who is still slightly afraid of the torch,
ashamedly.) Anyway, I actually used it yesterday for the first time
in ages. I was careful to check the hoses and connections and then
lit it up. I was so proud of myself. I was planning to work with it
today as well, but, am I in danger?
I might be miss informed, but i think i need some clarification on
the “Old acetylene is very dangerous” comment. I solder with propane,
but welding and metal sculptor are a hobbie of mine, even got
certified as a welder, but that is a different story. Never once do i
remember hearing, reading, or being told any problems with acetylene
aging. the main to concerns are a: keep the tank upright, and if you
really want the long explanation why e-mail me and i will tell you,
and be do not set your regulator above 15 (ok 20, but really think 15
and you are always safe) psi. As tanks age they need to be
recertified, NEVER oil regulators, torches, etc. But aging acetylene
is a problem? thats news to me. So point being, don’t be scared of
your torches, respect yes, but not scared, and unless someone can
clarify the point about aging being a problem with acetylene, well i
cant find any reference here in any welding book i have, nor do i
remember ever hearing that when i was studying for my welding cert.,
which yes, i did take a semester that covered gas welding and
brazing.