Settings I used to weld aluminum today...
amperage set to 133
A/C balance set to 65% dcen
A/C frequency set to 100
3/32% 2% thoriated tungsten ( like prefer 2% lanthanated these days but for some reason a new pack of 2% thor was in my tool box
A reader asked recently ..."what is the best size tig cup to weld aluminum"?
In Tig welding , there are lots of choices.
Water cooled tig torch or Air Cooled tig torch?
Big Torch? Little Torch?
Big cup or small cup?
Gas lens or standard collet body?
The good news is that no matter what the situation, there are cups and torches available to fit the bill.
Thankfully, for me, there is one setup I can use that will weld aluminum in about 90 percent of all applications I encounter.
A #7 gas lens cup with a small style torch.
Smaller size tig cups are handy for reaching into tight spots and for some applications are absolutely necessary. But sometimes a gas lens setup works better because instead of being able to reach a joint because of the small diameter of the tig cup, you can just extend the electrode further out and still maintain good gas coverage because of the ability of a gas lens to push gas further without loss of gas coverage.
Some info on tig torches....
A few large tig torches that use the large style collets and collet bodies are the #17 and #26 air cooled, and the #18 water cooled model.
There are gas lens collet bodies available for all and also shorter "stubby" collet bodies and cups available that make the large style torches a bit more useful.
Small style torches used to weld aluminum are the #9 air cooled, and the #20 and #25 water cooled models.
I like to use the smallest style tig torch I can that will handle the heat.
And by heat, I mean amps.
a wp 9 air cooled tig torch is only rated for about 125 amps.
but a wp 20 style water cooled tig torch is typically rated at 250 amps.
both torches are small but the water cooled sure is more capable.
Stepping up to the large style tig torches, a 17 style air cooled torch is rated at 150 amps and a 26 torch is typically rated at 200 amps.
But a 26 torch is huge compared to a wp20 water cooled model.