Actually Tig is cheaper than mig as far as the equipment goes. You can buy a regular constant current stick machine with DC output and spend about $60.00 for a tig rig and get a bottle and flowmeter and your ready to go.
I bought a power source on ebay for about $150.0 and made the welds shown at http://www.weldinginspectionsvcs.com/Dragster80Pics.htm .
If you buy a tig machine with a bunch of bells and whistles you have to pay for them. Many welds are made in the field with regular stick machines with a bottle of argon and a tig rig. I have welded carbon Steel, 300/400 series SS, Duplex Stainless, Inconel 625 and 825, and aluminum all with a stick machine set up with a tig rig. Scratch start, No ACHF, no remote control.
Hope this helps some.
Gerald Austin
Iuka, Mississippi
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