Welding Tips and Tricks

New to the forum - so maybe this has already been covered before. If so maybe someone can point me in the right direction.
That being said, my question "Is there ONLY ONE gas that can be used for AC and DC tig welding"?? All of my welding is hobbyist/home shop fabrication and I cannot afford/don't have space for assorted gas bottles. If it matters my system is an older Lincoln AC/DC 225 buzz box with a Lincoln Hi-Freq unit that I am trying to get set up for tig welding using an air cooled 200 amp torch. Any help/suggestions would be greatly appreciated.

Yes. Pure argon.
Helium is useful if you wanna clean up your puddle on aluminum or if you need to go a lot hotter than your machine is capable of welding with pure argon. But argon is all you need.

RamboBaby wrote:Yes. Pure argon.
Helium is useful if you wanna clean up your puddle on aluminum or if you need to go a lot hotter than your machine is capable of welding with pure argon. But argon is all you need.

Actually, using pure helium can do the opposite and make it all sooty, depending on if you use it on DCEN.

But that's not because of the gas....