As with TIG and most things its prep and cleanliness. Practice,practice and practice. Stainless Steel brushes. I haven't did much but the goggles with the correct colored lenses do help.
Go th the Henrob site, They had some videos on the torch and welding aluminum. https://cobratorches.com/
He also has the goggles that let you see the puddle and melted metal better.
You can rent the tinman tech gas welding of aluminum video at smartflix. http://smartflix.com/
Been there, probably broke it, doing that!
I am not a lawyer, and never played one on TV!
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