I stand to be corrected, I believe north america is the only location where c25 is used. Certainly good for the heaviest of structural work. Everything else gets best results with some c10 variant. That's what the rest of the world uses. Even add a couple percent of O2 which wets out the weld pool by dispersing surface tension. Also good for spray. Use it with confidence and ditch the c25.

 

90/10 is meant for spray transfer mode. That’s the gas to use for metal cor wire.
I wouldn’t bother using 90/10 for short circuit transfer.

 

100% CO2 provides the deepest penetration for short circuit MIG. As you add argon to CO2, the puddle becomes more and more fluid and the penetration diminishes. Some welders don't do short circuit MIG very well with C10, there's just not enough CO2 to keep the arc lit. That's one of the selling points for the new Miller 255; they tuned the electronics to handle C10 gas on short circuit MIG, so you don't have to change back and forth between gas cylinders to do spray or pulse.

 

100% CO2 provides the deepest penetration for short circuit MIG. As you add argon to CO2, the puddle becomes more and more fluid and the penetration diminishes. Some welders don't do short circuit MIG very well with C10, there's just not enough CO2 to keep the arc lit. That's one of the selling points for the new Miller 255; they tuned the electronics to handle C10 gas on short circuit MIG, so you don't have to change back and forth between gas cylinders to do spray or pulse.

That's interesting

 

It depends on what welder you have. To get the benefits of spray transfer a 250A or bigger machine is usually required. I have done it with a 200A transformer and I think some of the new 200A inverters will do it too.
You can also spray easier with 95/5 or 98/2 than 90/10. Be careful though I once got 95% Argon and 5% oxygen instead of 5% Co2 by mistake.

 

I'm running a powermig 300 so enough power to spray and has pulse spray mode too. I run .035 wire, I was thinking if the 90/10 can do a nice enough job on short circuit and also good for spray it's one bottle for both modes and a good all around gas. Would mostly be short circuit though so don't want to sacrifice that.

 

Well here in Europe / the Netherlands we use a lot of mix gas of 80/20 or 85/15 for structural steel / carbon steel, we weld all transfer modes with it. and you get a nice smooth weld and low spatter

almost no 85/25 is used with us.

for stainless steel solid wire we use a mix of:
Mixed gas Ar + 0.5-5% CO2 + 0.5-5% H2
Mixed gas Ar + 0.5-5% CO2
Mixed gas Ar + 0.5-3% O2

90/10 is used when the wire manufacturer proposes to weld with it.

we use almost no pure co2 gas, it does give a deep penetration, but this gives a lot of spatter and I think it is difficult to weld in the spray arc area

 

I don't Spray but I do short arc, pulse and twin pulse with 92/8 co2. 75/25 is less cost and short arcs well. The newer inverters run CO2 much better than 15 year old units. Pretty smooth and good for personal repairs on implements and the like. I get my gas for free so it's 92/8 for steel, 98/2 co2 for stainless. Tig and Push Pull Aluminum with Argon of course.

 

I use a C18 from AirGas for both short circuit and spray transfer. Nice clean welds on short circuit. It'll serve well for steel pulse spray as well.

 

The higher the argon concentration of your shielding gas, the more it costs.

 

Unless you add in Helium, then its even more expensive. $$$

Every time I get a new bottle of Tri-Mix, my boss lets me know its expensive( and its only a 120cf bottle ) With the usual sarcasm, what are you welding, gold back there in the shop ?

@ denlow - what do you find works the best on stainless wire solid wire, short ciruit (MAG) -16ga. to 1/4" 316 stainless. I've only used Praxair trimix which is Argon, Helium, and CO2. Are those other mixtures for Heavier plate?


Just curious.

 

This is a dumb question but readin this reminded me of something I heard about maybe 20 years ago when I had to get some bottles of mixed gas because the customer insisted I use dual shield wire for a dozer blade. So i went and got 6 bottles of mix gas, 75/25. The fella at the weld supply store said that in about 25 years we were going to start running out of Argon and it was going to get very expensive to get because Argon is created by the decomposition process deep underground. Have any of you fellas heard anything about this? I know it dont have anything to do with the original question, and I dont know a whole lot of stuff about gas mixes and such because I dont deal with the dual shield process very much.

By the way that was the only work I did with dual shield for him, he saw what happened in the wind up that mountain and bein as how I told him he was gonna have to get the bottles up there for me, and pay for that gas himself he wasnt happy. I talked him into lettin me use the Innershield I always used for another dozer blade and he liked it. I did another blade for him and and 2 buckets and he was sold on the Innershield. Im still probably one of maybe 2 or 3 fellas in this racket up here that uses it on a regular basis, most evryone thinks it gonna break or it aint no good because it dont get as shiny and pretty as the dual shield stuff. What the hell, shiny dont mean **** once that bucket starts diggin black coal and whatever else they run into.

Anyway I just wondered about what I was told 20 years ago and thought I would ask, my apologies if I jumped in where i have no busness

 

I believe it is a finite resource although I don't remember what the timeline is. I just hope it lasts till I start dribbling porridge down my chin again.

 

Argon is produced by air liquification. I doubt that we'll ever run out. Helium on the other hand comes out of the ground and is finite. That's why it is so expensive and getting more so all the time. Unless they find a way to capture it out of the atmosphere, we will run out

 

Yup, usually from processing natural gas and oil. The funny part is that helium is produced from radioactive decay of thorium (which we use as an alloying element in electrodes in TIG) and uranium, and at the moment we are at their mercy, as we cannot control it. The atmosphere has very little helium that we could extract; most helium just escapes into outer space. Our only hope is for the nuclear fusion reactors to finally go online as actual power producing stations. The main byproduct of nuclear fusion of deuterium and tritium nuclei is helium nuclei. We're close, but it will be another 20-30 years perhaps before the tokamaks and other designs finally become mainstream power plants.

 

Me too. I knew it was "mined" just had the wrong gas. We could always pipe some in from the sun...

 

Great discussion, guys.
Argon is the third most abundant gas in the earth's atmosphere at 0.934 percent. Check out this entry https://en.wikipedia.org/wiki/Argon. ~0le