proper gas

Mig weld with .035 ER70S-6 wire.12Ga. to 1/2" carbon steel. What gas should I use? I've been using 100% argon, but in some of your video's I've heard you mention a 75 25 mix. What should I use, and what are the differences?

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if you have been using 100% argon, you will think you died and went to heaven with a a 75 25 mix.

the arc will be much smoother and do what it is supposed to do...lay down and penetrate.

straight co2 works pretty well too if you take the time to set the voltage and wire feed right.