Stick vs. Push-Pull MIG on Aluminum: What You Need to Know

When it comes to welding aluminum, most people immediately think about TIG or MIG with a push-pull gun. Stick welding (SMAW) isn’t usually top of the list — but it can be done. In a recent CWB video, I compared welding aluminum with the SMAW and the push-pull MIG process, looking at the pros, cons, and results you can expect.

The setup: Joints, electrodes, and prep

For this comparison, I welded both lap joints and T-joints using several brands of 4043 electrodes. Regardless of the process, aluminum surface prep is essential. Before welding, I used a stainless steel wire brush to remove the oxide layer, and preheated the material with an Oxy-Acetylene torch.

It’s worth remembering that the oxide layer on aluminum does not conduct electricity. Running DC reverse polarity helps “clean” this oxide layer during welding, which improves arc performance.

Tips for stick welding aluminum

Using a constant current DC power source in reverse polarity, I pushed the amperage 10–20 amps higher than manufacturer recommendations. I also held a steady 90° rod angle throughout the weld.

Stick welding aluminum takes patience—these electrodes burn quickly, and it’s important to keep consistent pressure on the rod. Be prepared for some frustrations: slag removal is difficult, and hammering can ruin the appearance of the weld. Porosity is also common, even with good penetration.

Switching to MIG with a push-pull gun

Next, I welded the same joints using a push-pull MIG gun with pure argon shielding gas and spray transfer. Because aluminum wire is soft, the push-pull system prevents kinks by pushing the wire from the feeder while the gun pulls it through the liner.

One thing you may notice is black soot around the weld. This is simply oxides burning off, and it can be reduced with proper gas flow and gun position.

The results were clear: The MIG process produced smoother beads, consistent ripples, and toes that tied in nicely. While penetration wasn’t perfect in my test, the welds were cleaner overall compared to stick.

Comparing results

  • Stick (SMAW): Strong penetration, but porosity and uneven bead appearance are common. Slag removal is challenging.
  • Push-Pull MIG (GMAW): Cleaner welds, smoother bead profile, and less cleanup. Requires more expensive equipment and shielding gas.

And where does TIG fit in? TIG offers excellent quality, but also requires expensive equipment, shielding gas, and higher operator skill.

Key takeaways

  • Aluminum stick welding is rarely the first choice — but it can be done with simple equipment, if necessary.
  • Push-pull MIG delivers cleaner, more consistent welds, though it comes at a higher cost.
  • TIG remains an option for those with the skill, time, and equipment.
  • Various brands offer 4043 electrodes, and the results were very similar.

Aluminum may not be the easiest material to weld, but with the right process and preparation, success is possible.

Watch the video version of this post. (Available in English only at this time.) 

Kevin Roy

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