Using CO2/Argon for MIG Welding

[sven]

I converted my Lincoln 140 Mig to gas last night and did some test welds. OMG, I couldn't believe how much better welding with gas is! Flux sucks

Anyways, what do you typically set the pressure regulator to for the gas? My book doesnt specify this.

[Roxtar]

I go with about 35-40 lbs.
Wanna see some really cool welds?
Use the flux core wire with gas. Takes a little work to get it set right but the welds flow like butta.

[I HATE PONIES]

I plan to get the Hobart on gas this weekend. I have the numbers but alas they are out in the shop and it's cold as hell. You should be able to find them here. http://www.hobartwelders.com/weldtalk/

[R_Lefebvre]

Uh, don't you set your regulator for volume, not pressure?

My TIG welder generally runs at 25 CFH.

[OddBall...wolf...wolf]

I typically run my mig machine at 30 cfh but then again its a bigger gun than that. I would say 20 cfh should be sufficient unless there is wind or over head then it might need to be bumped up a bit.

[repete]

Iv'e always ran 15-17 cfh on my miller matic 250

[Roxtar]

Yea, I didn't really think first but I'm pushing through a 15' stinger from a Hobart 450
Welder sm.jpg

[sven]

How do you know if you're using too much or too little gas? In other words, what do you look for while welding?

[ptschram]

Too much gas flow will cause atmospheric air to be drawn into the weld and cause poor weld quality. Too little gas flow won't adequately shield the weld from the atmosphere causing poor weld quality.

I've had experienced welders tell me they purge their welders into their face and adjust for a gentle flow. I usually set for about 15 CFH if welding inside without a fan on and 20-30 is outside, the doors are open or I have a fan going.

[R_Lefebvre]

Yeah, and I've learned to purge before starting a weld if it's been a little while since the last weld. I wish there was a way to do it manually... I just hit the pedal for a sec holding the torch far away from the work, let the gas go a bit, move to the weld, then hit the pedal again.

Not sure how you'd do it on a MIG without having the wire come out?

[ptschram]

Originally Posted by R_Lefebvre

Not sure how you'd do it on a MIG without having the wire come out?

My welder has a "Purge" position.

[I HATE PONIES]

Hey PT how big is your tank? I am confused by all of the blah blah blah. How big of a tank will I need for medium use but still fit in a welding cart. I don't think I need one as big as the torch tanks but I don't want one too small either.

[ptschram]

Originally Posted by I HATE PONIES

Hey PT how big is your tank?

Lemme go measure it.

[sven]

I bought a 40. The guy told me if I set the volume at 20, it would last 2 hours of weld time.

[I HATE PONIES]

I ended up getting a 92. I am curious to see if it will last as long as a 10lb spool of wire.

[I HATE PONIES]

I don't know how I ever welded without gas. This is an absolutely amazing difference and it's cheaper. It is plain to see that the difference between novice welding and professional welding is not only experience but largely the equipment.

[antichrist]

Originally Posted by ptschram

I've had experienced welders tell me they purge their welders into their face and adjust for a gentle flow.

That's what I do for both MIG and TIG. Of course with MIG I have to be sure to disengage the wire feed drive wheel first.

[antichrist]

Originally Posted by I HATE PONIES

It is plain to see that the difference between novice welding and professional welding is not only experience but largely the equipment.

Actually it's more experience than equipment.
As for MIG vs. fluxcore, they are both "professional" processes and both have their place.
Take your MIG outside to repair some equipment on a windy day and tell me how much better it is than fluxcore.

[I HATE PONIES]

Originally Posted by antichrist

Actually it's more experience than equipment.
As for MIG vs. fluxcore, they are both "professional" processes and both have their place.
Take your MIG outside to repair some equipment on a windy day and tell me how much better it is than fluxcore.

I have both just in case. I don't plan to weld outside though.

I am just saying that the difference between flux core and gas is like the difference between flux core and stick.

The biggest plus is the lack of smoke inside.

[jeepfiend]

Don't be too quick to bash the stick!! You can just about train a monkey to run a squirt gun, but to really learn to weld, you should start with a torch, move to the stick, and then on to the squirt gun. When I got certified, they wouldn't even let us touch the wire feed until we certified with the stick. Reason being, the stick really teaches you how to manage the puddle and understand what the metal is going to do with the heat applied. The torch even more so. I use my wire feed quite a bit, but I still like the buzz box. Since my wire feed is only a 110V unit, I always resort to the stick for anything heavier than 1/8". I've never been too good overhead, but it's really just a practice thing. I don't spend the time welding I used to, so things aren't as pretty as they used to be, but I still really like my stick welder.

[antichrist]

x2 on learning stick frist to be good at MIG. Way to easy to get cold lap with MIG.

Originally Posted by I HATE PONIES

I am just saying that the difference between flux core and gas is like the difference between flux core and stick.

I underatnd what you're getting at. My point was that it actually is weldor skill more than equipment.
A skilled weldor can do a good job with crappy equipment (god knows I've used some crappy equipment over the years), but I don't care how many dollars you throw at equipment for a crappy weldor, you'll still have crappy welds.

[maxyedor]

Originally Posted by R_Lefebvre

Yeah, and I've learned to purge before starting a weld if it's been a little while since the last weld. I wish there was a way to do it manually... I just hit the pedal for a sec holding the torch far away from the work, let the gas go a bit, move to the weld, then hit the pedal again.

Not sure how you'd do it on a MIG without having the wire come out?

Most if not all the newer tigs have a pre-flow setting, usually you only need .1sec, but if it's been sitting a while I step it up to 1 sec. for the first weld. On a mig you just turn the wire-speed way down and point it away from the work, you do end up wasting a few inches of wire, but there's a few thousand feet of wire on a spool, so who cares about 6-8 inches?

I have my mig set to 12cfh in-doors and 19cfh outside, use as little as possible without contaminated welds, no sense in overshielding, all it does is waste gas and money.

[antichrist]

Originally Posted by maxyedor

I have my mig set to 12cfh in-doors and 19cfh outside, use as little as possible without contaminated welds, no sense in overshielding, all it does is waste gas and money.

Too high a flow rate will also distort your arc and lessen weld quality.

[I HATE PONIES]

Originally Posted by maxyedor

Most if not all the newer tigs have a pre-flow setting, usually you only need .1sec, but if it's been sitting a while I step it up to 1 sec. for the first weld. On a mig you just turn the wire-speed way down and point it away from the work, you do end up wasting a few inches of wire, but there's a few thousand feet of wire on a spool, so who cares about 6-8 inches?

I have my mig set to 12cfh in-doors and 19cfh outside, use as little as possible without contaminated welds, no sense in overshielding, all it does is waste gas and money.

I just flip the tension adjuster down and hit the trigger. The gas comes out but the wire doesn't. The gas comes out so fast that I think it may not be needed. I do it anyway just to be sure.

On the flow rate the welder shop guy told me to run 30cfh. It is working O.K. so far but I will try turning it down if I can get away with it.

[antichrist]

The Weldor's bible:
https://ssl.lincolnelectric.com/linc...asp?prodnum=PH