read these
viewtopic.php?f=60&t=77
http://www.ckworldwide.com/tech-3.pdf
http://www.thefabricator.com/Consumable ... fm?ID=1024
look here
ask questions here, because they know more than I do about many parts of the welding arts
http://www.millerwelds.com/resources/co ... ay.php?f=4
http://ehs.unc.edu/manuals/ehsmanual/h4-12a2.pdf
72novaproject
"Stainless should be welded with 100% argon. It is practical for most shops and hobbyist. There is a helium mix that is better but way expensive and it has to be purchased in larger quantities you would never use so forget that. Stainless is welded with straight polarity or NCEN (Direct Current Electrode Negative).
One thing you should consider is back gassing the weld joint. Tape up the ends of the collector with cardboard (away from the welding heat) and run a hose inside to fill it with argon. The back side of a non back gassed stainless joint will crystallize due to oxygen exposure. A common term is sugar behind the joint. It is also important to be very aware of pre flow and post flow when welding stainless. It is hard to make yourself hold the torch over the weld for 5 seconds after the arc stops but you got to do it.
I bought stainless wire for my mig and tried it with 75/25 once. It will weld stainless but it isn’t pretty. Hence the tig purchase.
Aluminum is welded with 100% argon and AC current. Most welders have an adjustable balance control (time at DCEN/DCEP) to achieve the best cleaning action and penetration. That is the reason AC current is used.
when your talking about mig/tig shield gas flow rates
gauge on right side indicates tank pressure
gauge on left side indicates flow pressure
15-20 psi flow pressure is usually adequate, but ask your local miller dealer for tips/advice, and gas mix info
"