Hi I've been using CO2 for welding mild steel but i ran out and so decided to try out Aargon instead as Ive heard of some people using it. The problem was that it seemed to react with the wire as the arc was formed - making a mess of it all. So should i be sticking to CO2 only or should i use CO2 and Aargon mix or am i doing something wrong with the Aargon gas.
Cheers
Rob

Usually for mild you wouldn't use 100% argon, you can use CO2 with a small amount of Argon. It makes the welder neater but the penetration is less compared to 100% CO2.

I used to use Co2, Then I tried Argon shield

I wouldnt go back despite having just paid the anual rental this week

i remember using pure argon once and the wire just became a green haze - i think it needed more wire speed. Tend to use an argon/Co2 mix now.

I was using 5% argon/CO2 but have gone back to using CO2 and can hardly tell the difference apart from a bit more spatter. I'll live with it.

CO2 is fine for just steel, but Argon CO2 mix is the best all round gas, will deal with steel, and stainless steel. If you want to weld alluminium then straight Argon is a done deal. IMHO Ray

CO2 makes a 'harder' arc but I use it for mild & stainless without any problems. Argoshield makes for neater welds but the disposable bottles only seem to last 5 minutes and the CO2 bottles have more gas in them for less money.

Pure argon is for TIG and special alloys only, for MIG you need the CO2 mix to give the arc sufficient 'burn'

Stainless welded with co2 will not give stainless welds as the gas introduces carbon into the weld, it will stick it together though if you're not fussy about the appearance.

I use a mix of 50% CO2 and 50% Argon - very happy with it, and I can use it with stainless as well. Very clean welds on mild steel, as well...