Stick welding vs flux core on structural steel - which one do you reach for first?

I got into it with a guy on my last job in Gary about which process is better for heavy structural repairs. He swears by dual shield flux core for everything because it lays down faster and he says stick is outdated. But I ran some tests on a 2 inch plate repair last month and the stick welds all passed bend test on the first shot while the flux core had porosity issues on two of them. The flux core was definitely faster, probably saved me 30 minutes per joint, but the cleanup and prep time ate into that. I also had to swap out liners twice on that job which I never deal with when I'm running 7018 rods. Am I missing something with the flux core setup or is stick still the way to go for the tough stuff? What do you guys reach for when you need it to hold?

3 comments

3 Comments

the_avery16d ago

Man, stick all day on heavy structural. Flux core has its place but not when you're talking about 2 inch plate and critical repairs. That porosity issue you ran into isn't rare either, I've seen it happen on site welds when the wind kicks up even a little. The time savings on flux core get eaten up fast when you're fighting with wire feed issues and having to grind out bad passes. Stick is slower but it just works on dirty, thick steel.

robinj2916d ago

Bringing up the site weld thing is huge, thats where flux core really falls apart for me too. You can have everything dialed in perfect inside the shop but the second you're outside with a slight breeze you're chasing porosity like crazy. I've seen guys try to run a little shielding gas with flux core to fix it but then you're messing with dual shield setups and it just complicates things. Stick might be slower but I'd rather spend the extra time on a clean weld than gamble on a repair that needs grinding later. On thick dirty steel especially, the reliability of stick beats any speed advantage flux core pretends to have.

daniel_walker15d ago

Those 0.035 dual shield wires with a 75/25 mix in the field can be their own headache too, you're swapping gas bottles and dealing with frozen regulators as soon as the temp drops. I keep a box of 7018 rods in my truck for any outdoor work over 3/8 plate, just saves the headache of grinding out a bad bead later.