Too much or too little gas flow?

by Paul
(Chicago, IL)

I'm new to tig welding and have a diversion 180. How do you know what the proper amount of gas flow to use on each project? How do you know if your using too much gas?

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for a # 6 cup about 15-20 cfh is about right.

smaller cups need less proportionally and bigger cups need more.

steel is very forgiving and when too much gas is used, air will be drawn in to the argon and will cause porosity.

not enough will give the same symptom.

on aluminum, too much gas will cause a very loud arc noise and it will be hard to get a puddle on thick aluminum.

way too much gas on aluminum will cause contamination just like on steel.

not enough gas will cause contamination in the puddle also.