I have been MIG welding since I was about 15, which is darn close to half of my life. I really wanted to step up my welding game, and after saving forever, I finally bought myself a TIG welder about a year ago. The welder came with a pressure regulator and after some trial and error, I decided that much like MIG welding 15-20 psi seems to work alright for most TIG welding situations. I have since used up what seems like an EPIC amount of Argon & Argon/CO2 mix (compared to MIG welding). I assumed that was normal…
So I’m talking to my friend the other day who is also new to TIG welding, and using what seems like an exorbitant amount of gas (sound familiar?). He told me that his welding supply store just informed him that he was supposed to be using a FLOW meter not a PRESSURE meter. Ooops. They told him that once he swaps over from pressure regulated (only) to flow regulated, his gas tanks would last far longer. They even gave him a free tank filling.
I was confused by this because why would both of our TIG welders come with pressure regulators if we really needed flow meters? Seems stupid right? I decided that I needed to do a test. I got my tank filled, because it was obviously empty again, grabbed some party balloons at the local pharmacy, and into the garage I went!
I began by attaching the balloon to the TIG torch with a zip tie.
Then I attached the Flow meter to my newly filled tank, and set it to flow 15 CFM with the TIG pedal fully pressed.
I then grabbed the stop watch and hammered the foot pedal to the floor for 5 seconds. The welder was set to 3 seconds of post flow for the entire test as well for a total of 8 seconds of gas.
Then I swapped balloons, zip tied it the same way, and hooked up the Pressure regulator to the same new tank. I set it to 15 PSI because that is usually my go-to pressure for whatever reason.
It was now time to bury the pedal for 5 seconds again and hopefully see a big difference in the balloons.
Hmmm, odd. Looks and feels almost 100% identical.
So now what? The volume of gas that comes out in 5 seconds (really 8 because of post flow) appears to be the same between my pressure regulator and my flow meter. Does this mean that my flow meter won’t actually save me anything? What is the correct one to use? If the same volume of gas comes out of the torch, why is one better than the other?
Then I got bored…..
So I hooked up a balloon to my old MIG welder.
Plugged my 14 year old, well used pressure regulator into my new tank, and set it to 15 PSI.
5 second of “welding” later, I ended up with this.
Disappointment. Obviously the gas was leaking from a plethora of places. I wonder if I should fix that? It welds great, but it does have about 1 million hours on it. That may be something to think about again when it is not -3 degrees outside.
The follow up questions:
1) Why do people use Flow instead of Pressure regulators when TIG’in? If they push out the same volume of gas, what’s the difference?
2) If people use Flow meters for TIG welding, why don’t they use them for MIG welding?
3) Did you know how awesomely sealed up a TIG torch is? Those balloons would have stayed full forever if I left them alone. Niiice.
Somebody School Me On This!!