Gunner Gunner Asch fired this volley in
:

Of course 12 is too dark. Somewhere between 7-9 is more the range for
average tig welding.

No, not "of course". I've never done any TIG welding. I was going on
advice that apparently wasn't accurate.

The only book I have on GTAW recommends a dark shade for aluminum work, at
least a #10. Ok... so it was too dark...

In an unfamiliar process, start safe, work back.

LLoyd