CO2 or mix for MIG

I prefer straight CO2 for everyday welding with 0.035, C10 (90%Argon/

10%CO2) for spray transfer process with 0.035 and yes it can be done with a standard GMAW set-up...C25 is a good all-round mix for everyday welding that will provide good results with 0.030, 0.035, 0.045 straight wire and dual shield wire.

straight CO2 does require better technique OR more grinding, but in my experience, you do get a stronger weld with it than with C25, and it's cheaper.

it's going to come down to your personal preferences and/or abilities.

if you're getting lots of spatter with straight CO2, you may need to adjust your flow, your heat and/or speed settings, your technique or all of the above....but seeing as how no two welders run exactly alike, it could be that your particular machine is not suited for running CO2 /shrug/

-- Big Ben BS266 the "hot metal is fun" Slug

You DO get around doncha ? I'm using CO2 with .025 ER70S6 , got C25 too but hardly ever use it . I'm using a 110V Lincoln WeldPak 100 , it doesn't handle over 1/8" well unless I preheat .

why yes sir, I do...LoL

there's folks I know that swore I lived 150+ miles from where I really live because I've popped up on my scoot so often...

as fer weldin' I'm currently limited to an old AC unit...it's a red one...it welds passably well...at Ma's place, an el-cheapo 110 gasless unit at Dad's, and a $10,000 TIG/stick unit that I never heard of at the firehall....funny as hell...they spent all that dough and nobody but me knows how to run the darn thing....the outlets alone ran about $1500 apiece...try to teach (older) country boys how to do anything other than a "farm weld" is challenging... at least they know that they don't know anything about the mo-sheen or the processes...woulda been easier if they had just got a $4-6000 miller wire/stick unit and got a spool gun for aluminum /shrug/ ah well, at least they got the right gas for it

-- Big Ben BS266 the "sometimes I just show up" Slug

92% Ar 8% Co2 better weld quality and the ability to spray transfer weld. You need 10% or less Co2 for spray transfer, or so I was told.

Thank You, Randy

Remove 333 from email address to reply.

I have some dual shield wire that does spray with 100% CO2. But I believe you are right for solid wire.

Dan

yep...like I said, I've used C10 (90% Argon/10%CO2) for spray transfer welding....been a while tho'

had two identical Millers in the shop...both had their "favorite" settings that worked right for spraying, but could be approximated as "really HOT and really FAST"....had to swap to an .045 tip to reliably spray with .035 wire, something about the magic way that copper has of shrinking when heated...

I used to build water tenders... a basic 20 foot "A" model tank set for duallies (about 2000 gallons) had about 80 feet of spray transfer weld applied to inside seams a "B" model with similar dimensions would require about 56 feet of same

eyes sure would be tired after a day of spraying

-- Big Ben BS266 the "feelin' gritty just thinkin' about it" Slug

I started off in 1980 with a new MillerMatic 200 and a chop saw, grinder, and a BIG bottle of CO2. I welded for years never knowing that there was a mixed gas for MIG. Then I got into different things, and had a call to do about 500 footrests for slot machine stools. They wanted them VERY pretty, and convinced me to get the mixed gas. The cost of the job paid for more than the bottle, so I tried it. Actually, it does produce a prettier weld, a narrower bead, and less spatter, but not all that great for the cost. IIRC, just a pass with a cup knot brush, and it was clean of spatter. The spatter did stick pretty good, but not so much that the brush didn't knock it off.

It's just time to go get some gas, and the guy told me he'd make me a deal on my owner tank, which I bought from him, in exchange for a CO2 tank and regulator. Plus, the CO2 can be filled in the little town I live in, rather than driving a 60 mile round trip to go to the city.

But, hell, if I find a cheap CO2 tank, I'll probably end up with two. A guy can't have too many tools, even if you only use if once a presidency.

Steve

"Big Ben" wrote

With my MillerMatic 200, I finally used .045 liners exclusively for .035 wire, as they did not clog up nearly as fast. Those 12' Tweco liners were a bit spendy. I did not notice any difference in performance, and I welded with that welder for 14 years.

Steve