I'm finally getting around to setting up the tig and I need to get a cylinder of gas. It'll be mostly steel welding, what should I get, straight argon or 25% co2? What's the difference?
Ok, how about this... My welder is a ESAB 350 mpi, does both MIG and TIG... should I get 2 cylinders, or is one gas good enough for both? I won't probably use the mig side for a while, but it's good to know.
You can experiment with other gases for TIG, but CO2 AIN'T one of them - will weld for **** - I know 'cause I tried it once. With TIG you can buy cheaper gases for SOME applications, but for what little morr Argon costs it's the best becuase you can weld anything with it and NOT have to keep multiple cylinders of gas for each metal. Bottom line - I'm with everyone else!!!!
i wasn't trying to save money, it's the same price for argon or 75%argon/25%co2.. I just wanted to know why there's an option, why choose one over the other? Everyone says Argon for tig and the mix for mig... but why?
from what i have been told, the Co2 helps keep the weld heat contained to a smaller area, which in theory keeps the warpage to a minimum... now if thats true or not, i cannot say, but i got it from two different experianced welders
Ive used mig gas in a pinch w/tig and I think it worked but only because I ran out of argon. I keep two bottles with my rig. I would suggest straight argon for your machine. No need to keep switching over. Im going to do the same when the 75/25's gone. I believe the shielding for tig needs to be more pure due to the electrode/ heli-arc application. A different type of fusion where the arc is actually further from the metal vs. direct contact as with a mig. I could be wrong, and do not know much more than that. Maybe someone else can correct me or fill in the blanks. Good luck.
I got a fancy diploma on my wall from a tech. college for welding and sheetmetal fab. At the fab shop I worked at, we always used separate tanks, a 75/25 mix for MIG and straight Argon for TIG. Sad thing is, I really don't know why. I can get out my AWS manual if you really need a technical answer. Plus, I'm pretty sure straight Argon is a lot more expensive, so it might be worth it if you're gonna do a lot of wire welding.
i always thought that MIG wasnt a direct contact between the electrode(wire) and the joint to be welded? kinda always been told it was like a "drip" of molten filler wire forced into the weld puddle via the Arc, and thats why inverted MIG is a PITA to do and always comes out looking like an orangutan's *** or am i just splitting hairs here
well here a true to life answer cause i screw up all the time in my shop we do a lot of aluminum mig and tig stainless tig steel mig and tig With aluminum you must use 100% argon for mig and tig otherwise you make a mess if you dont believe me try it or just forget to swap tanks with stainless tig all i have ever used is argon never got the tanks mixed up on that one but i do remember grabbing an aluminum rod while hurring to do a stainless repair for a customer there was lots of grinding to follow with steel mig if you use 100% argon the weld just doesnt seem to lay out what i mean is it just kinda likes to sit on top of what your welding with steel tig there is no problem with 100% argon that i have found hope that helps bill
N8inks, By "saving money" I meant to suggest that when TIG welding you can theorectically minimize your gas costs by using the optimum gas for the material at hand - aluminum welds "better" with some argon/helium mix. The addition of helium gives you a "hotter" weld. Which leads us to the EFFECT that sheilding gases have on your weld. For instance when MIG welding with straight argon you get a penetration shape that is kinda oval (if memory serves me) and add CO2 and the penetration gets narrower and deeper. SO bottom line the type of gas can allow you to change the penetration characteristics of your weld. Not only that but it can allow better penetration with the same current on your machine - as in the Helium/argon example mentioned earlier. If you wanted you can MIG with straight CO2 - it will weld kinda "dirty" but it will weld nonetheless. CO2 is one of the cheaper gases (or it should be if your supplier isn't gouging you) - Argon is generally one of the more expensive gases, BUT!! it will pretty much allow you to weld anything so it is a common choice unless you want to store several cylinders. For a business welding miles and miles it makes a big difference - for us home guys it just isn't worth the h***le. I don't recall the technical answer to your question, but late one night I ran out of gas for my TIG and I was hot to trot to finish my project so I glanced over to my MIG rig and thought - hey it works for MIG how bad could it be for TIG - I mean they're both "INERT" gases right?? Well Yes and No. CO2 is actually LESS inert than Argon - that's what makes Argon superior (as I understand it) anyways there I was desperate to continue TIG welding with a full bottle of 75/25 Argon/CO2 next to my MIG. SO I hooke dit up - I mean how bad could it be??? Well let me tell you I did FORCE it to weld but it was ****. Fought me every step of the way and in the end was a BAD idea that I WILL NOT do again. One thing I have started to learn withage is patience and planning. I now have a spare Argon bottle so I am not dead in the water at some future midnight thrash. Bottom line when TIG welding: CO2 = ARGON = Nothing to do with the cost unless you put a price on aggravation!!! Just thinking out loud!!!!
well, I'm convinced.. thanks for sharing that experience... I'm the type of person that likes to know how and why everything works, but sometimes it's just not necessary... it just works.
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