How to Weld With Flux Cored Wire

For most at-home welding projects, a flux-core welder is the best choice. As opposed to GMAW (gas metal arc welders), which need a large tank of shielding gas to accompany the welding machine everywhere, fluxed-core welding machines are small and portable. Instead of using a shielding gas, the wire itself contains a material that, when burned, shields the weld from contamination. Flux-core welders are a little more temperamental than GMAW machines, but practice is the key to getting it right.

Difficulty: Moderately Challenging

Instructions

Things You'll Need:

• Flux-core wire feed welding machine
• Welding mask
• Welding jacket
• Welding gloves
• Slag hammer
• Angle grinder

Preparing to Weld

1. Set the wire speed and voltage on your welding machine to the proper settings for the thickness of metal you're using. Each machine should have a chart for reference.

2. Put on your safety equipment, including a welding mask, jacket and gloves. Wear long pants and inflammable shoes. Make sure you have no exposed skin. The arc from the welder produces UV rays that will cause sunburn.

3. Position whatever you want to weld so that it is secure and you can stand comfortably when working on it. Also, remove anything from the work area that could be knocked over. Once you flip down your mask, you won't be able to see anything to avoid them.

Welding with Flux-Core Wire

4. Press the trigger on the welder so that about 1 inch of wire is sticking out of the nozzle. Don't let the wire touch anything metal while you're pressing the trigger, or it will arc.

5. Position the welding gun so the wire is touching the seam you want to weld. You want to pull the gun along, not push it, during fluxed-core welding, so start at the end of the seam farthest from you.

6. Flip you mask down by nodding your head quickly forward. Try not to move your welding gun because you won't be able to see to line it back up.

7. Press the trigger to start the arc. Pull the gun toward you, moving it in a slight side-to-side motion. Let go of the trigger when you reach the end of the seam.

8. Inspect the weld. If you didn't finish the whole seam, or if you need to go over the weld again, hammer the slag off of the weld with the slag hammer. If you don't, the next weld won't penetrate properly.

Tips & Warnings

• With fluxed-core welders, it's important to pull the bead, not push it. Fluxed-core produces slag as it cools. This slag interferes with weld adhesion, so you want it cooling behind your bead, not ahead of it.
• Welding creates a lot of heat. Don't touch your welds immediately after you've completed them. Keep your welding project away from areas where someone might accidentally touch it until it is completely cooled.

References

• MIG vs. Fluxed-core
• Flux Core Video