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Nordic1
12-29-2004, 03:12 AM
So whats better to use as a shield gas with a mig welder: 100% co2 or 75% Co2 and 25% argon... thanks!

OverkillZJ
12-29-2004, 11:24 AM
So whats better to use as a shield gas with a mig welder: 100% co2 or 75% Co2 and 25% argon... thanks!

steel = c25

robselina
12-29-2004, 12:03 PM
for argon/co2 mix is supposed to be better but many people get away with co2 only w/o adverse effects...

JeepinHank
12-29-2004, 06:20 PM
CO2 isn't so great for welding thinner stuff. It gets hotter and will cause burn thru quicker. If you're welding near the top-end of your welder's range, you might want to consider it.

I run the C25 (CO2/Argon) mix, and I'm happy with it.

nate
12-31-2004, 01:20 AM
I use Co2/Argon.

My brother runs a CO2/Argon mix with 2% oxygen and he said it works better for him. This is with a PowerMig 300 though, so I can't say you'd really notice with a smaller/cheaper machine.

robselina
12-31-2004, 05:57 PM
My brother runs a CO2/Argon mix with 2% oxygen and he said it works better for him. This is with a PowerMig 300 though, so I can't say you'd really notice with a smaller/cheaper machine.

huh? That doesn't make much sense to me at all. O2 in the mix would cause greater porosity, that's why we use shielding gas to displace the O2 or am I getting something backwards?

Jim311
12-31-2004, 08:44 PM
CO2/Argon mix is at Tractor Supply in a 30 cubic foot bottle for 99 bucks. Is this a good deal?

nate
01-01-2005, 04:53 AM
It's quite possible I misunderstood him, I'll have to ask him again.

Here is some good info on MIG gas.
http://www.weldreality.com/MIG_welding_gases.htm

robselina
01-01-2005, 04:29 PM
It's quite possible I misunderstood him, I'll have to ask him again.

Here is some good info on MIG gas.
http://www.weldreality.com/MIG_welding_gases.htm

Turns out you're right and there is a three-part argon/co2/02 mix but this guy really disses it :lol:

He basically said argon/co2 mix is all you'll ever want or need.

Quote:

"If you take an argon CO2 mix and add oxygen to that mix, you simply increase the weld oxidation potential and lower the unique weld energy potential and the gas dissociation properties offered by carbon dioxide.

The oxygen addition in the three part gas mixes will influence the weld fusion profile. Typically a narrow finger penetration profile is produced.

The narrow finger fusion weld profile freezes rapidly trapping gas reactions, increasing the weld porosity potential."

Like I said, it eliminates the benefits of the CO2 and increases weld porosity. Aparently the design is all snake oil....

nate
01-01-2005, 05:18 PM
So whats better to use as a shield gas with a mig welder: 100% co2 or 75% Co2 and 25% argon... thanks!

The 75/25 mix is actually 75% Argon/25% CO2.

Seems to be what most people run.

The dude in the link I posted seems to think an 85/15 mix is better for mild steel though.. hmm. :?:

Nordic1
01-02-2005, 09:52 PM
I have a 20 lb bottle of CO2 already so I think I am going to start out with it... eventually I'll switch to the argon mix and see which one runs better on a lincoln 135 (hey 110v is all I got for now).

Mtn WJ
01-04-2005, 12:10 PM
According to the link you will be ok with the co2 only mix with the smaller welder. I have the same welder and like it so far. I am also using co2 mix for thinner welds. I will probalbly go to an argon mix afterwards when I start the body work on an old truck. Just in case you were not aware you will want to use flux core for thicker welds with a smaller Mig. I noticed this on my own and then I read it in the manual. The Lincoln 135's rating for the thicker metals is based on flux core wire. I like the 135 because I can take it to were my truck is stored and use it there because there is only 110v.

I also like the option of using the co2 tank in my Jeep with my Ready Welder II if needed in a pinch.

It also said if you weld at higher amps than 150 you should use the mix gasses. This seems to be were the Co2 breaks down and you get more splatter. To me one of the bigger benifits with mig besides being able to weld thinner materials with less warping is getting rid of all that flux smoke.

Nice link on the gases by the way.

Jim311
01-04-2005, 10:45 PM
Yeah, for the type of stuff I do, I think my 135 110v will work out well. So far it's had more than enough power. I've been using the flux core wire with pretty decent results. Even when/if I decide to move up to a 220v welder, I'll still probably keep my 110v just because it's so portable and I can use it ANYWHERE there's an outlet for the most part.

AprilzWarrior
02-05-2005, 02:57 AM
Boy oh boy, thats a lot of answers with no real truth above.


C25 is indeed 75% Argon/ 25%Co2 (Carbon Dioxide)
Perfect for Mild Steel, with Solid Cored Wire.


Now the Tri-mix of O2/Argon/Co2 is just special, nothing that any of us should need.


On the other hand, Tri-Mix of Argon/Co2/Helium is common for Stainless mig.



Does that help ?

AW

CJ Guy
02-17-2005, 04:00 PM
for mild steel, i run 75% / 25%

nate
03-09-2005, 08:47 PM
My brother is a welder and a machinist by trade, so it's not like he is just getting this info 2nd hand.

He told me that he finds the Tri mix... (Stargon is what it's called) welds better than C25, though it is a bit more $$. Just personal preference really.

rubicondave33
03-09-2005, 09:08 PM
I use Stargon with my machine. A buddy of mine told me to try it out, and he swears by the stuff. I really like it myself, yeah it's expensive, but the results are nice too.

AprilzWarrior
03-11-2005, 02:30 AM
Helium in the Tri Mix causes more heat in the weld, hence a smoother mixture of the metals. Sorta like preheating then mig welding.