I have a problem and would love to hear some suggestions.
I am using a Hobart Handler 140 Mig welder with a CO2 shielding gas. I'm using a solid 308L .030 Stainless wire.
First, I think I'm using the wrong gas? I believe I should be using a Argon Mixture of 75 Argon, 25 CO2, or possible even a Try Mix.
What I am trying to accomplish is to weld a nice fillet on stainless steel tubing. I am consistently getting a very bulbous looking joint, which is not concave, or beveled. To me, this fillet looks like it belongs on an outside corner and not an inside corner. How can I achieve a relatively decent looking fillet on an inside corner. I'm not concerned with super small even welds, just a functional halfway decent looking weld. The tubing I am using is a typcal 1" round stainless tubing used on boats. I'm not sure of the guage, but it's about 1/16 of an inch thick,.
Any help, suggestings, and ideas would be greatly appreciated....
Co2 really stinks for welding stainless. Use 98-2 Argon/ Oxygen. The O2 will help "Heat" the puddle and make up for the lack of power from you HH140. O2 is a reactive gas that helps the arc carry more heat to the puddle. Tri mix works good to, but not really needed in this case. Stainless takes more heat than mild steel and will be a bit more difficult to weld, but it's totally do-able.
Good luck!!
rharms,
Yes, you are using the wrong gas. Try an Argon gas with 1 - 2 % Oxygen.
Not sure what the tradename etc will be as I am on the other side of the world but there will be plenty of people on this forum who can help you out,
Regards,
Shane
The Tri Mix gas for this application would be 90% Helium, 7.5% Argon and 2.5% Carbon Dioxide. Flow rate should be about 20 cubic feet per hour.
Use a push gun angle. Push the gun towards the direction of travel should flatten the weld.
Check the owner's manual for the correct Electrode Positive polarity.
If the wire should slip on the drive rolls, you may want to use their V-knurled drive roll. This means the drive roll pressure can be alot less for good feeding.
Keep the wire stick out past the contact tube less than 1/4 inch. And modify the nozzle so that the contact tube is about 1/8 inch past the end of the nozzle.
I would recommend a 98% Ar - 2% O2 gas misture. Without more details (welding parameters, travel speed, position of welding) it is hard to make any recommendations other than the gas mixture. You might have better luck with a GTAW process on this small of diameter and thickness tubing.
Chuck
I think's it's unanimous. Change gas to 98/2. It's whats recommended in the filler metal specs.
357max,
Don't you think the 90% helium mixtures are expensive for the minimal gains you see from it's use? I have found that 69-30-1 Ar/He/Co2 works just as good (almost the same) at 20% less cost. Now, we surly are not welding high tech stuff at our shop, and maybe in specific areas the 90 He has it's benefits, just not in our shop....yet...
No disrespect intended, just my .02 worth.
Mark
No disrespect received, I'll have to try the Argon with 1 & 2% O2 & CO2 for stainless steel short circuit transfer. I have always used the Helium/Argon CO2 Tri mix and know that it works very nicely for the short circuit transfer. The Argon 1 & 2% O2 & CO2 I have only used for the spray and pulse spray transfer. Though I prefer the Tri mix with Argon 66%/ Helium 33%/ CO2 1% for spray & pulse spray transfer. Who fills the Ar 69/He 30/CO2 1 for you? You are right, helium mixtures are getting more expensive due to the shortage caused by the balloon fillers.
We get that mix from a local shop that has ties to BOC. I would assume that the mixing is done by BOC, but I will find out when the truck gets here today. Now, 1-2% O2 will still weld good in short circuit too, it's not limited to spray.
Hi rharms,
I would offer a suggestion as ssbn727 always does....go to Ed Craig's WeldReality website and get a real education on welding gasses. I find the information provided by Ed Craig to be absolutely sound and proven. You will really learn various welding techniques and procedures that will enhance your weldability....Denny
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