If you search google for “What Tungsten Should I Use for AC TIG Welding Aluminum?”
And…you read the first few results, you might just walk away more confused than ever before.
Some web sites recommend pure tungsten or zirconiated for tig welding aluminum with transformer style machines and other tungsten types like lanthanated or ceriated for tig welding aluminum using inverter style machines.
But does pure tungsten really perform better than others with transformer tig welders?
The internet is full of opinions on this so why not add one more?
Here is my opinion on pure tungsten:
I never liked pure tungsten…not even on older transformer machines. ( But I will add that most of my welding on transformer tig welders was with miller syncrowaves and other square wave tig welders.)
It’s true that pure tungsten rounds the tip nicely.
But what I dont like about pure tungsten is that it just won’t carry enough amperage for my preferences.
Every time I tried to use it on production jobs, where I needed about 250 amps, a 1/8” pure tungsten just wouldn’t hold up.
And since I was using a 20 style water cooled tig torch, finding 5/32” hardware was hard to find back then. The company I was working for didn’t have 5/32” tungsten or hardware anyway.
So that’s one of the reasons I never really liked pure tungsten.
Just having a nice rounded tip was not worth the drawbacks to me.
I also found that I liked zirconiated much more than pure tungsten on transformer tig welders because it would ball just as nicely as pure but it carries amperage better.
A 1/8” 2% thoriated tungsten can handle AC welding of aluminum at 250 amps with no problem…you just have to round the tip a certain way before you start welding.
2% lanthanated handles high amperage even better
I also found thru testing that 2% lanthanated tungsten works well with both inverters and older transformer design tig welders …(at least on the miller syncrowave 250 and the Lincoln squarewave200.)
This video shows how to round 2% thoriated tungsten for tig welding on AC
