why is the arc so much softer on stainless when I use 75/25 gas. The weld bead is high and the arc is not as aggressive. I am welding watertight welds in 20 gauge 304. A seam about 6" long. I can't get a special mix with a 20 cu. ft. tank, only argon or 75/25.
Try what the welding supply store call tri mix for ss.
the suppliers will not do the small tank in any special mix gases. they say I must go to the "m" size tank. What will the tri-mix do on plain steel. If it would work, then it could justifly the bigger tank of tri-mix. Otherwise I'd have a bunch leftover with no immediate need.
try argon if they will fill your tank with argon only.
it will perform better than the ar/co2 mix.
when you finish the stainless job go have the mix put back in your little tank.
THAT IS WHY WELDING IS A PROFESSION TO BE STUDIED. THERE IS ALOT TO LEARN. WHICH WELDING PROCESS DO I USE? WHAT MATERIAL AM I GOING TO JOIN? THE TWO COMMON GAS PROCESSES THAT WE USE GTAW AND GMAW EACH REQUIRE DIFFERENT GASES FOR DIFFERENT MATERIALS. RULE OF THUMB, TRI MIX FOR SS, C02 OR 75/25 FOR MILD STEEL. THERE ARE MANY OTHER GAS COMBS ON THE MARKET ALL FOR DIFFERENT USES. WELD IS A PROFESSION TO BE LEARNED IT IS HARD TO TEACH OVER THE INTERNET. CHECK WITH YOUR LOCAL COM. COLLEGE OR HIGH SCHOOL FOR HELP. IF THAT IS OF NO HOPE EMAIL ME AND I WILL TRY TO ANS SOME OF YOUR QUESTIONS. GARY
Hi Bzzzzzzzzz,
>>Why is the arc so much softer on stainless when I use 72/25 gas<<
As compared to what? We routinely use 75/25 Ar/CO2 with FCAW on stainless steel with good results.
What process are you using? GTAW? GMAW? FCAW?
I'd like to assume that your not using GTAW and 75/25, but one never knows.
Filler metal?
>>The weld bead is high and not as aggressive<<
Again, compared to what?
Bead profile can be affected by many different factors. Voltage, wire speed, travel speed, oscillation, just to name a few.
More information would be good. Can you elaborate?
Hope this helps
Dale Simonds
If you are using the GMAW process, then 75/25 is the wrong gas for SS. While a tri-mix is the optimum gas under some circumstances, it is generally not required under most circumstances. An Ar-2% Oxygen mix will probably do everything you want. You should be able to get this in any size tank.
Hope this helps
Regards
Niekie Jooste
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