I tried playing with aluminum welding rod today. Welded two 1/8" flat pieces. The weld looked nice. I then took a strip from the two welded pieces and tried to break it. it broke instantly. As it turns out, the weld was full of luttle bubbles, like a bagel. Not useful for anything except non load bearing applications, if that.
Hi, Do you know anything about what alloy of aluminum you are welding? Some series alloys are classed as unweldable. I have been practicing with and building stuff out of 6061 with decent results.
I have heard that with 6061, you need the metal in the weld region to be at least 50% rod. This results in a much larger bead profile then is proper for a steel weld. Ernie or somebody with more aluminum experience than I have can probably give you a more detailed/better answer.
All TIG welding really needs clean parts before welding, and aluminum especially. I get noticably better results if I wipe the weld area down with an acetone or lacquer thinner soaked rag. After the solvent evaporates, I use a stainless steel wire brush in a cordless electric drill to clean oxide away in the weld region and weld it quickly after cleaning. Note than you can weld aluminum without all this cleanup, but the cleanup gives you better results.