[ConKbot of Doom]

Originally Posted by Greg Needel

just a side note for people who don't know.

when welding aluminum you use AC current which is produced by the alternator but there are diodes in the circuit which basically turn it into DC. while this will work for steel welding don't think you are going to get any good aluminum beads with it

Just to add onto that, even if you remove the diodes to get AC, you wont be doing aluminum either. You need high-frequency AC to break through the oxide coating that builds on the puddle and will actually rectify they current.