Mig settings for pure CO2 welding

[Tarponslayer]

I just got a tank of pure CO2 and I wont make that mistake again. In the mean time does pure CO2 need different settings compared to CO2/Argon mix for the same job? How much nozzle pressure and wire speeds etc...

[PJinNJ]

Hold on

If you had a Miller Passport you'd be smiling right now. I use them both and the straight works best with the passport.

[hankj]

I just got a tank of pure CO2 and I wont make that mistake again. In the mean time does pure CO2 need different settings compared to CO2/Argon mix for the same job? How much nozzle pressure and wire speeds etc...

What is it about the CO2 that you don't like? I've had great success with it welding mild steel.

Generally, it likes higher voltages and wire speeds than C-25 for like thicknesses. Flow rates are the same.

Hank

[Tarponslayer]

What is it about the CO2 that you don't like? I've had great success with it welding mild steel.

Generally, it likes higher voltages and wire speeds than C-25 for like thicknesses. Flow rates are the same.

Hank

Its seems to spatter and spark so much more then the Argon mix. Thats what made me wonder if I had my settings way off. Thanks for the info.

[Benesesso]

That means you have gone beyond the "short arc" mode of metal transfer and are in globular. Back off the voltage and WFS until you don't get spatter.

Not welding fast enough? Go to thicker wire.

Which welder do you have?

[hankj]

Tarponslayer,

Take the same steps with CO² shielding gas as you did with C-25 to find the sweet spot. Belive me, there is a sweet spot for CO². It's all I've ever used on the MM135, and I weld with virtually no spatter!

I'd second guess Benesso's recommendation to jump up in wire size. It depends on your machine. Some (like my MM210) like a diet of one wire. The macine's characteristics make the difference.

Hank

[westval]

Tarp,
I prefer CO2 over a mix. I've never had a spatter problem with it. I don't do any of the art type stuff though, so maybe what I call "no spatter" would seem severe to others. My Miller, Linde, and Air Procucts machines run very good beads with CO2. The price diference is well worth it IMO.

[Mike W]

I also get very little spatter with CO2 and .035 wire with my Hobart. I first time I tried C25, I had a lot until I dropped the voltage down. I haven't seen any data concerning voltage settings for different gases.

[Bowtieman31]

CO2 is the way to fly! It's inexpensive and will give you deeper penetration. Been using it for more years than I'd like to remember. Never had any problems with it.

[Dan]

I also get very little spatter with CO2 and .035 wire with my Hobart. I first time I tried C25, I had a lot until I dropped the voltage down. I haven't seen any data concerning voltage settings for different gases.

Mike,

Typically, for the same (roughly) amperage value, CO² is going to require 1 to 2 volts more than a C-25 gas mix. BTW, you CO² guy are alot like the guys who swear stick is the only way to go.

[Mike W]

LOL Dan. I figured you would show up sooner or later. What is the theory behind needing to drop the voltage for C25? I was trying some C25 and .024 wire the other day on some .064 wall tubing. It was working but seemed a little cold. I finally took the CO2 and .035 and used it, I felt better.

[Dan]

LOL Dan. I figured you would show up sooner or later. What is the theory behind needing to drop the voltage for C25? I was trying some C25 and .024 wire the other day on some .064 wall tubing. It was working but seemed a little cold. I finally took the CO2 and .035 and used it, I felt better.

Mike, I think this will give you a good enough answer. http://www.esabna.com/EUWeb/MIG_handbook/592mig4_2.htm

[Mike W]

That is one of my favorite sites, good info there. Leaving out spray arc, CO2 delivers more heat to the weld compared to C25.

[Dan]

That is one of my favorite sites, good info there. Leaving out spray arc, CO2 delivers more heat to the weld compared to C25.

Mike, sorry man you aren t going to convert me over to CO². I started out using CO², I actually ran strictly nothing but CO² for the first ten years. Then I tried a bottle of C-25, and haven t had a desire to go back to CO² since. I just prefer the nicer arc of C-25. With my power sources, producing sound fusion between the basemetal and weld metal is no problem with C-25 on the material thickness range that I weld on. You won't catch me trying to weld 1/4" with a little 120V unit. It just isn't going to happen. Not that CO2 is going to help a 120 v unit that much. The output voltage just isn t there to take advantage of what CO2 has to offer over C-25.

That MIG handbook on ESAB's site, came with my Migmaster 250 as a paper back book. If ESAB sells it to the public I'd recommend it along with the hand book that Miller offers, both are very good.

[Mike W]

10-4 Dan. I guess I am so used to CO2 that it is like an old pair of boots that fit well. From your experience what would be the maximum voltage that a power supply would need for spray arc?