Gas Usage - TIG vs MIG

**JB4x4** · 12-13-2010, 05:24 PM

Hello,

I have been a long time MIG welder (10+ years) and have just started to play around with TIG. I recently got a WeldAll 250 and a fresh bottle of Argon "S" size. Funny thing I was hoping you guys could answer for me. I am able to put many pounds (don't ask me for sure, it comes in 40 lb rolls) of wire through my MIG doing production work, and an "S" bottle will last for months. I have been playing around with this TIG for a few weeks, and might have used a lb of rod tops and the bottle is almost empty.... I swapped regulators and they read pretty close. The gas flow has been set at approx. 15 cfm the hole time. And the post flow is anywhere from 5 to 10 secs. My welds don't look to be "gassed out" like a MIG with to much flow. Any ideas would be appreciated.

Thanks,
John

tomsign · 12-13-2010, 05:52 PM

John have you tested the unit it self to see if it is leaking while you are welding

**JB4x4** · 12-13-2010, 06:05 PM

Funny, I never thought of leaks. I guess I was curious if gas usage could (would) be that high. I will check connections.

tomsign · 12-13-2010, 06:08 PM

its amazing on how just a little leak can wast so much gas

**SICFabrications** · 12-13-2010, 06:55 PM

2 things.... turn your gas down to about 10 to 12 unless youre using a large lens, that will help alot... if your tig welding, you shouldnt be outside and your pace is alot slower then mig, so you dont need the cfm comin through the nozzle quit as fast...

next thing is turn that post flow down a lil more.... you dont need quite that much post flow unless youre welding above 250 amps or welding continuously for minutes on end non stop around 200 amps.... 3 to 5 second post flow is adequate...

tomsign is also correct, time to check for leaks as well.... soapy water around all the connections except inside the machine, but a "flap" of bathroom tissue is a great tell all for leaks too in places that water shouldnt be

**JB4x4** · 12-16-2010, 06:54 PM

Well, I got to my TIG today and believe I found my problem..... I borrowed as gas meter that can be used at the nozzle of a TIG/MIG that goes to 40 CFM. Pulled the trigger once and it PEGGED!!!!!! Guess what I learned, the Longevity included regulator is calibrated in LPM???? So, the "15" I was reading converts to 32 CFH. Now I know why I was using so much gas. I guess I shouldn't have assumed I had an "English" calibrated flow meter. Time for another bottle of gas.

JB

---------- Post added at 07:54 PM ---------- Previous post was at 07:52 PM ----------

And just in case anyone was curious, the conversion factor is not quite 2:1 (2 CFH = .943 LPM)

JB