Originally Posted by Leadsled124
Also the wire in your mig welder is harder than the rod used in tig welding,
The wire is exactly the same, 308/309/316 is the same if it comes in 36" lengths or 44# spools. Same goes with steel and aluminum. Now, the finished weld might have more or less ductility, but that is dependant on the parameters and the weldor.
Originally Posted by bigusnickus
You will also need a different shielding gas for this job (98%Argon 2% Oxygen would be the most preferred).
Im not so sure about that... 98/2 generally is used on heavier sections. Tri-mix will give a much nicer bead appearance with the small machine.
One last thing, if both welds are of sound quality under identical conditions then TIG and MIG are equal in strength. However it is MUCH easier to F-up a MIG weld.
Finishing up my B.S. in Welding Engineering.