75/25 gass

[HAWK]

fun4now,

Here's a copy of Andy's response on shielding gas with MIG welding of stainless:

ASKANDY
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Registered: Sep 2002
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Posts: 483
Stainless nitty gritty.

bail has the best mix at 90he 7 1/2ar 2 1/2co2 or some dealers stock a 90-8-2. Both short arc SS fine. As a "get by gas" you can do the 75ar/25co2 or the 80/20 you mentioned before but you kill the corrosion resistance. The reason you would like to reduce the Co2 is that it tends to pick up carbon however it is slightly needed to increase penetration. The high HE addition will help to spread the arc cone to prevent high ropey beads and will also reduce the possibility of undercut. "Generally" the 98ar-2o2 is a spray gas. I personally didn't like the way 98-2 short arcs. It was too ropey for me.

All in all the tri-mix is the way to go. Most dealers can get it and if they tell you they can't....well I'd go to a more competent dealer!

Good luck

Andy



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03-22-2004 09:15 PM

[HAWK]

fun4now,

Welcome to the forum!

A 98%argon/2%oxygen works well for stainless on larger machines with inductance controls. A tri-mix will probably suits your needs better since the MM135 has a preset fixed inductance. About 1/8" will be your limit on stainless with this machine. Do a search for stainless and you should find some good info on the forum. Congratulations on your MM135 and have fun!

[fun4now]

75/25

dont have a project yet ,just wanted to know if i would need another bottle for stainless. i have a miller matic 135 for tinkering in my home shop. this is the first mig i have ever used big change from flame. and just wanted to try it on stainless. soon i hope to be making go-carts / minie dune buggys. im retired and bored

[MAC702]

Short answer: Yes.

In most cases, though, you may not want to. I believe it leaves a soot and also discolors the weldment. There are those here who have done it and can chime in, but expect to hear something like that.

What is your project? What machine?

[fun4now]

hi all new to list and mig welding please bear with me as i will probubly ask some stupid ????? first ?? is can u use 75/25 on stainless?? and i hope im doing this right!!!