Hi,

I am learning to MIG weld and have of course chosen aluminum because I always go the hard route first. I took about 2 hours and played with the machine to get the voltage/current right and I am leaving good beads but I need some help. The first 1/2" of the bead is crap but the rest looks great, is this the arc heating the metal? If so should I preheat? I am doing 1/8" 6061 aluminum with about 20V and 100A, penetration is great but I want the weld contour to be good, help if you can, also add any suggestions you may have.

Thanks,

- Mike