It is currently Sat Feb 24, 2018 6:04 pm Advanced search

Mig with Co2

mig and flux core tips and techniques, equipment, filler metal

Mig with Co2

Postby JHenze646 » Sun Apr 30, 2017 12:30 pm

I have seen a couple threads where there is reference to running solid wire with 100% CO2. What are the pros and cons of this practice? Is there any special considerations for running straight CO2?

Thanks for the help
Active Member
Posts: 25
Joined: Thu Sep 08, 2016 1:44 pm

Re: Mig with Co2

Postby Otto Nobedder » Sun Apr 30, 2017 12:37 pm

The biggest "pro" is cost. 100% CO2 is much less expensive than, say, 75/25 Ar/CO2.

The biggest "con" is increased weld spatter to clean. The initial appearance of the bead is less attractive, too, but a wire wheel fixes that right up.

It's been so long since I welded straight CO2 that I can't guide you on differences in settings, though I recall they weren't much different.

User avatar
Otto Nobedder
Posts: 8409
Joined: Thu Jan 06, 2011 11:40 pm
Location: Near New Orleans

Re: Mig with Co2

Postby Farmwelding » Sun Apr 30, 2017 12:41 pm

I've done some straight CO2 and it isn't a ton different. If you look at the Miller weld calculator, you have to increase your voltage some to get a similar weld profile/strength. For someone who is doing stuff in their garage, I honestly would reccomend it. As Steve said-cheaper, and you don't necessarily have to get bottles filled at a welders supply store. Have a store that sells and fills paintball gear you can go there.
A student now but really want to weld everyday. Want to learn everything about everything. Want to become a knower of all and master of none.
Instagram: @farmwelding
Posts: 1466
Joined: Thu Mar 10, 2016 11:37 pm
Location: Wisconsin

Re: Mig with Co2

Postby Artie F. Emm » Sun Apr 30, 2017 12:53 pm

Another 'con' is co2 welds hotter than argon-co2, so it tends to melt through thinner materials such as auto body panels.
aka "RTFM"
Artie F. Emm
Posts: 674
Joined: Thu Jul 24, 2014 7:53 am

Re: Mig with Co2

Postby MinnesotaDave » Sun Apr 30, 2017 1:16 pm

I use 100% co2 pretty often. Once dialed in it welds very well - set 1 to 2 more volts over argon/co2 mix.

Spatter accumulates in the nozzle, so nozzle dip and a little cleaning once and a while is the deal.
Dave J.

Beware of false knowledge; it is more dangerous than ignorance. ~George Bernard Shaw~

Airco 300 - Syncro 350
Invertec v250-s
Thermal Arc 161 and 300
Tried being normal once, didn't take....I think it was a Tuesday.
User avatar
Posts: 1691
Joined: Sun Oct 27, 2013 10:57 pm
Location: Bemidji MN, U.S.A.

Return to Mig and Flux Core - gas metal arc welding & flux cored arc welding