Can I mig weld aluminum without using a shielding gas?

Any problems outside of the extra oxidation?

This is not anything structural, just a couple of tack welds to hold a spacer in place. I am changing jobs in a week and I may not have access to a tig anywore. The machine shop mainly work with steel so I am not sure if they are set up for working with aluminum.

A $10 spool of wire is a lot cheaper that buying a tig setup for myself since I only need to do a few tacks. I am sure later I could find plenty of uses for a tig.

nope, you have to use argon.

what about the old skool AL welding rod with a oxy-acetalene.....

Never used this myself ....  would you have access to a stick welder?

http://store.cyberweld.com/alel40.html

the one that uses Oxy/ace torch is like silver solder for alum, the Buzz box rods for alum do NOT seem to burn well enough to lay a nice bead, but then, i dont think much of the welders skill that i seen use em either.

Nope.  Aluminum forms very strong oxides that will inhibit a puddle from forming.  You'll just make a mess.

  Mig uses argon.

damn, guess I will have to spend some money.

it is actually cheaper to pay a tig welder $10-20 per job than to buy a TIG rig and stay good at welding AL

i got a nascar TIG welder about ...8 miles from the house....

Right now all I need to do is tack some things. One problem is my lack of availability to take the parts to a shop. I may be able to machine them as one piece instead of welding them together.

This all may be a mute point once I get my recent medical bills.