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Discussion Starter #1
Boys are mig welding in the shop and getting bubbles/holes in the bead



Not enough gas? Steel too cold?


Once in a while it does this cheese wiz deal. Need pro advice


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:dunno: I ain't there,, but,,, :dunno:

if I were to guess,,
either gas flow rate,, or torch angle is causing the gas flow to suck air (oxygen) into the weld puddle,,,

BINGO,, porosity,,, :flag_of_truce:
 

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Definitely gas related, what CFH are you running? I find 25 is a good number for my older Miller 210 and my current 252.
 

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First guess would be gas coverage, it looks clean enough to weld better than that. If the surface under the plate you're welding on is dirty, it can pull bad stuff from there.

I'd have someone watch the gauge as you actually weld, not just what you set it at. I had one regulator that would show 20cfh and then drop to 10 after about an inch of welding. Took calling a friend over to figure it out, he saw the needle drop when I started cursing the puddle getting bad.
 

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Are you using the correct shielding gas? I use C25 for almost all of my welding. It’s pretty universal and flexible. If you were using straight Argon, you’d get those porosity issues.
 

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Maybe forgot to turn the gas on!:unknown:
 

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Maybe forgot to turn the gas on!:unknown:
Or maybe it’s not making it to the puddle thru the hose, something not connected?
 

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Discussion Starter #9
Turned the gas up to 25 and it does better. They were dipping the tip in that anti slag gel so cleaned it and use more gas seems to work




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Are you using the correct shielding gas? I use C25 for almost all of my welding. It’s pretty universal and flexible. If you were using straight CO2, you’d get those porosity issues.
A real weldor can MIG weld clean steel with straight CO2 and not get porosity like that. Maybe the spatter is a little worse but the welds are just as good as with C25. :flag_of_truce: :hide:
 

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Are you using the correct shielding gas? I use C25 for almost all of my welding. It’s pretty universal and flexible. If you were using straight CO2, you’d get those porosity issues.
A real weldor can MIG weld clean steel with straight CO2 and not get porosity like that. Maybe the spatter is a little worse but the welds are just as good as with C25. :flag_of_truce: :hide:
Maybe I am a real welder but I would consider myself more of a novice. :laugh:

I weld with 100% CO2 because that is what I have. I am a home brewer so I have several CO2 tanks for my keggerators. I just "borrow" one when welding and it works fine. I don't get bubbles like that. What I get is a little more spatter. The weld still looks good. Nothing that a flap wheel on a angle grinder can't clean up in a single pass.







I would also lean toward a gas issue. Maybe you have a bad tank. I have seen that before. I also use a flow meter not a regulator.

Another tip that I don't know if it applies but throwing this out because I have seen it be an issue that hasn't been mentioned yet and I don't know your welder. With the Hobart welders they ship with flux core wire. Since they ship this way they have the polarity on the welder set for flux core. When you go with solid wire with shielding gas you have to reverse the polarity. If you don't you get crappy welds. Like I said I don't know your welder to say this is the issue but something quick to check.
 

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The anti slag gel is a double edged sword, a little goes a long way. That said, usually after you dip it, you'll have some inclusion in your weld, not too much but it's there... next, as others have said is gas flow. Also, they might have had a fan on to blow the fumes away, which can blow your shielding gas away too...

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A real weldor can MIG weld clean steel with straight CO2 and not get porosity like that. Maybe the spatter is a little worse but the welds are just as good as with C25. :flag_of_truce: :hide:
Maybe I am a real welder but I would consider myself more of a novice. :laugh:

I weld with 100% CO2 because that is what I have. I am a home brewer so I have several CO2 tanks for my keggerators. I just "borrow" one when welding and it works fine. I don't get bubbles like that. What I get is a little more spatter. The weld still looks good. Nothing that a flap wheel on a angle grinder can't clean up in a single pass.







I would also lean toward a gas issue. Maybe you have a bad tank. I have seen that before. I also use a flow meter not a regulator.

Another tip that I don't know if it applies but throwing this out because I have seen it be an issue that hasn't been mentioned yet and I don't know your welder. With the Hobart welders they ship with flux core wire. Since they ship this way they have the polarity on the welder set for flux core. When you go with solid wire with shielding gas you have to reverse the polarity. If you don't you get crappy welds. Like I said I don't know your welder to say this is the issue but something quick to check.
Yup, my bad. I meant Argon. I edited my post. :good2: Thanks for catching that. :hi:
 

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When I was in the shipyard it was no gas, low flow of gas, or the fan blowing on me. It was mostly a fan being my problem.
 

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Never mind on the polarity issue. I know it causes issues and one of the first things a new welder should double check when changing wires. Sounds like it is more spatter than even when welding with 100% CO2.

How To Set Your MIG Welding Polarity Settings - Learn Welding | MIG Welding Training

Here are some tips on the bubbles. Seem to mainly point to the gas issue as we have been saying. Make sure the gun is clean, no leaks at any connection, avoid drafts. There is a reason arc welding is still a thing, it works much better outdoors and with dirty steel. MIG is more fussy.

The Basics: MIG Troubleshooting | Bernard
 

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Discussion Starter #16
Thanks guys. I knew I’d get some good hands on experience here. That’s one of the things I really like about GTT. Everyone is here to help. You guys rock


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I’ll bet when your tank was full you were getting good beads. You probably have a flowmeter but the pressure will play into it. I have a much much larger cylinder but it is getting down around 300 psi right now and at that pressure I have to run my flow meter around 30 instead of 15 or I will get exactly that. With the smaller tank you’re going to see that variable much quicker.
 

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...or with a fan blowing on them.......
This was going to be my guess. I learned a long time ago that a fan can really mess up your welds when migging. Welding is kind of an art form, but so is learning how to direct a fan on you that will effectively help cool you during a hot day of mig welding without having it disrupt your gas flow. Most welders I know will put a fan on a stand by where they're welding and have it pointing towards their head. Even having a fan cut on low and 15-20 feet away from you can mess up your welds if you have it pointed towards where you're welding.
 
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