Along these same lines, stick welding with the widely-available AC welders. Also, what rods work best overall and for different positions and currents.

I just burned up a bunch of 6013 and 7014 trying to find a good combo for some 1/8" wall tubing and flat bar. 7014 is easy to use, but didn't seem to penetrate very well. 6013 wanted to burn holes in everything. I accidentally made some decent welds with the 6013, but damned if I know how or why it happened.