Mild to stainless (304/316) use 309L wire & tri-mix. The weld will have a black soot left after welding, but will wire brush off.

304, 308, 316 to itself, use the same wire as the base metal. Gas is the same. 316 is non magnetic, I'm not sure about 304/308. I know a couple stainless grades are magnetic.

 

To summarize:
304 or 316 to Carbon Steel: 309 filler
304 to itself or 316: 308 filler
316 to itself: 316

I recommend 98% Argon 2% CO2 gas.
A lot of guys use 90% Helium, 7.5% Argon, 2.5% CO2, which is great for short circuit transfer.

I hope this helps.

 

You will not be able to weld stainless steel with that welding machine because it does not produce enough heat. Sorry.

I tried once and I even bought expensive tri mix gas, Turned the settings on the machine to extremes and had the right filler wire the smallest size. Lincoln 110V wire feed.
I was trying to join 22 gage stainless (2 inch X4 inch plates( and when the machine was turned up all the way if you moved very fast it would make a weld that looked like tooth paste that came out of the tube.
I tried every combination of settings travel speed and filler wires. NO DICE.

The 220V machine will work but you still will not get the results like a TIG machine will get.

309 filler wire is used to join steel to stainless steel.
If the filler wire has 308 "L" that means low carbon and that is good to keep the carbon content low as possible.

BTW when welding 304 base metal use 308 filler. Always try to use one step higher on the filler material.
And 316 use 316 filler wire.
ALSO innersheild wire is hollow in the center filler with powdered flux.
In stainless it is called duel sheild.

 

You will not be able to weld stainless steel with that welding machine because it does not produce enough heat. Sorry.

I tried once and I even bought expensive tri mix gas, Turned the settings on the machine to extremes and had the right filler wire the smallest size. Lincoln 110V wire feed.
I was trying to join 22 gage stainless (2 inch X4 inch plates( and when the machine was turned up all the way if you moved very fast it would make a weld that looked like tooth paste that came out of the tube.
I tried every combination of settings travel speed and filler wires. NO DICE.

I find this hard to believe, however I don't own that machine so I want to take your word for it. However 22 gauge is pretty thin stuff and I would think that any welder could stick that together regardless of how small it was.

 

What happens if you try to weld stainless using 75/25 argoshield?