Hey guys, I have a TIG and a MIG welder at work. We don't have extra bottles to backpurge. I was wondering what it would be like if I TIG welded, argon, and backpurged with the MIG gas, co2 and argon mix I think. I forgot the exact mix. I think its 75% co2 and 25% argon

 

When I back purge while TIG welding I have a T piece fitted after the regulator with a flow meter that is used to purge, so only needing one bottle. Not sure how purging with the co2 mix would go, if you use the co2 mix as your main shielding gas it just burns the tungsten tip out in seconds. I'd try on some scrap tube to see how it works, the co2 mix is cheaper.

 

No, it is not recommended.

 

Oh, I never thought of that, thanks! So I would just need another regulator off that also so I'm not using too much gas to backpurge

 

the whole purpose of backpurging is to prevent oxygen from oxidizing the weld metal the same as purging the weld puddle side through the TIG cup

so think about why you wouldn't want to use CO2 ...