WHAT GAS TO USE WITH FLUX CORE WIRE

J

JC Daniel

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I have a lincoln welder with flux core wire and I want to use gas to make the weld a little better on body panels, A guy today told me that I can not user gas with flux core wire and another said he uses Co2 with flux core all the time with great results. I would appreciate any help you guys can give me.
 
I've never used gas with FC wire. To reduce splatter use a good FC like Lincoln. I found that has little splatter when using on sheet metal.
I'd be careful with CO2 on body panels being that is thin gauge metal and you will likely burn through. I use pure CO2 only if I need deep penetration on thick steel, otherwise argon/CO2 mix is better on sheet metal, if using a gas as a shield.

Mike
 
If you have gas why not just pick up a spool of MIG wire instead of messing with flux core wire?

Don
 
You need to understand what shielding gas and flux do. Flux is a substitute for shielding gas. The flux shields the weld from atmospheric air to prevent contamination. Same thing as a shielding gas such as 75/25 Argon/Co2. You want better welds? Don't use flux core on sheetmetal. Use solid wire with 75/25 Argon/Co2. Guy you are talking to is either full of it or ignorant. FLux core on sheet is dirty, you have to scrape the slag off, it will never be as clean as solid and you can't weld as thin a material as you can with solid. FLux core is designed for thicker material in a windy enviroment. Mig welding sheetmetal you want to use 75/25 Argon CO2 with solid wire. .023-.025 is the most popular. .030 will work as well.
 
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JC Daniel said:
I really appreciate the help guys, I am going to get some solid wire and 75/25 argon.
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You will be glad you did. Flux core is great for farm machinery out doors where the wind will blow the shielding gass away. For auto restoration I would definitely take Chris's advice.

Does anyone here know if Easy Grind wire is still available? ESAB used to make it but I have not seen it lately? I used it on the Chevy floors and body mounts and liked it even though it does behave a little differently.
.

John
 
John Long said:
You will be glad you did. Flux core is great for farm machinery out doors where the wind will blow the shielding gass away. For auto restoration I would definitely take Chris's advice.

Does anyone here know if Easy Grind wire is still available? ESAB used to make it but I have not seen it lately? I used it on the Chevy floors and body mounts and liked it even though it does behave a little differently.
.

John
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Easy Grind is no longer available.

Don
 
JC- Just check that your Lincoln is capable of using shielding gas. Some of the small Lincolns out there are flux core only.
If it is set up for gas it should have a fitting on the back for the gas hose, have a nozzle to use on the MIG gun for the gas and a flow meter/regulator.
 
The fella that mentioned using co2 might have got confused and thought you were talking about dual shield (example esab 7100) which has flux but requires gas as well. But it's not for thin steel
 
The local gas supplier is trying to sell me straight Co2 and said it would be all I need for body panels. I have told him that I need argon co2 and he says I don't need it.
 
JC Daniel said:
The local gas supplier is trying to sell me straight Co2 and said it would be all I need for body panels. I have told him that I need argon co2 and he says I don't need it.
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That’s crazy imho. Mix gas for welding steel body panels.

Don
 
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JC Daniel said:
The welder has the fitting on the back with the hose on guages but what should the nozzle look like?
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Dark photo but its the copper tube shape on the end of the gun around the contact tip.
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I did see a Lincoln that had a cap to protect the contact tip when using flux core (no gas) in addition to the gas nozzle.
You want the 75% argon / 25% Co2 mixed gas for the solid wire. Get either .023" or .030" 70S-2or6 wire for the sheet metal.
OOps Chris already gave you the info on the gas mix and wire size.
 
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by me they recommend the tri mix. I have no luck with penetration with solid wire and tri mix so maybe they are wrong. I have tried 023 030 and it just sits on top of the panel. The .035 flux core works best. If I try to add tri mix to that the penetration goes away.

I know if you are doing aluminum you need pure argon, but I can definitely tell you I get no penetration with the tri mix. Just if that makes any sense to anyone.
 
anotheridiot said:
by me they recommend the tri mix. I have no luck with penetration with solid wire and tri mix so maybe they are wrong. I have tried 023 030 and it just sits on top of the panel. The .035 flux core works best. If I try to add tri mix to that the penetration goes away.

I know if you are doing aluminum you need pure argon, but I can definitely tell you I get no penetration with the tri mix. Just if that makes any sense to anyone.
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Tri-mix? I only used that once to MIG stainless sheet. What machine do you have? Did you try turning up the voltage? Even the smaller 120V machines should work fine on 18-20 gage steel or auto sheet metal without needing flux core. Flux core does give better penetration for an equal heat setting over solid wire and gas. Sounds to me you are not far off, maybe experiment on scrap metal to find what works. I've seen some machines work better with .023" wire and some like .030" on sheet metal. Does your machine have any charts with recommended setting? Some times that will get it close.
 
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