The Stovebolt Site Forums The Shop Area Paint and Body Shop filler over weld

If flux core wire(mig) is used on body work does the flux have the same result as the flux used in brazing? Does it cause the filler to come off in time. I use a lot of flux core on other stuff and my cylinder is straight argon for aluminum use. Now I need to weld some sheet metal that needs filling.

While pure argon might not work as well as a argon CO2 mix it is far superior to flux core. Use the Argon for both just be sure you have good penitration.

the co2 helps with the penetration of the welding, or if you can get a bottle of pure co2, even pick up one for those drinking fountans,may work better than the pure argon

Pure CO2 is not really a good idea. Weld done with pure CO2 are crack prone. Stick with the argon and turn up the heat.

To answer your question 46, I would think any flux residue should be removed prior to bondo or painting. I think you will be better off with the shield gas, as others have alluded to. I tried to save on the cost of a gas bottle and initially used flux core wire in my MIG but it splattered like crazy (regardless of the polarity) and made crappy welds. I make much better welds with a CO2/argon mix.

I usually use the straight argon with the flux core any way. Just did not know if i would be able to weld sheet metal with non flux core and pure argon. On fenders penetration is not a real issue. They are thin to start with. I will still use the flux core most of the time since it will be on equipment, angle or chanel. I bought the argon to weld aluminum just hoping i could cheat a little on thin sheet metal.