How to MIG Weld Aluminum

MIG welders are extremely versatile welders that can handle a wide variety of projects. However, before you buy a spool of aluminum wire and try MIG welding aluminum, you’ll want to learn about the particular challenges and adaptations you’ll need to make before attempting to MIG weld aluminum.

Aluminum-mig-weldingImage Source: ThomasNet

Use 14 Guage or Higher for MIG Welding Aluminum

The one challenge you’ll face when trying to weld aluminum is that a MIG welder may have too much power for thinner sheets of aluminum. A good rule of thumb is that you’ll weld aluminum that is 14 gauge and higher. Thinner aluminum will need a pulse setting for a MIG welder. Otherwise, use a TIG welder.

Torch Position for MIG Welding Aluminum

A 10-15 degree torch angle will be ideal for MIG welding aluminum. You’ll also want to push your torch while welding rather than pulling it. A straight, steady torch movement is ideal for MIG welding aluminum so that the impurities stay outside of the weld puddle. Some welders suggest inching forward and then pausing before inching forward again so that your final weld has a neat, uniform appearance.

Use a Spool Gun to MIG Weld Aluminum

A spool gun will save you a ton of time and aggravation since aluminum wire is too soft to effectively feed through a MIG machine. It will keep getting jammed, and you’ll have a frustrating time at it. Spool guns attach to your MIG gun and then feed the wire right into the torch. 

Use Spray Transfer for MIG Welding Aluminum

You’ll use a longer electrode stick out for MIG welding aluminum and the melted aluminum will be sprayed into the weld puddle. If you hear the crackle you usually hear when you’re welding steel, you’re doing something wrong. Your wire feed speed is most likely too fast. Though it’s usually ideal to start a little on the fast end and then adjust the speed as you go, having too fast a wire speed will add too much metal and possibly damage your metal work piece.

Clean the Aluminum Before MIG Welding

Solvents such as acetone are usually ideal for cleaning metal, but if you have a lot of mill scale, you may want to grind down the metal first before prepping the weld.

Use Straight Argon for Aluminum MIG Welding

Though some gas mixtures can be used as a shielding gas for MIG welding aluminum, the majority of situations will call for a simple tank of argon. You’ll need to weld with argon using reverse polarity or DCEP.

Pick Up A Complete MIG Welding Set Up

MIG welding aluminum requires materials and parts beyond what comes with a typical MIG welder. The best way to ensure that you have everything you need for the lowest price is to pick up an Aluminum MIG welding set up from Baker’s Gas and Welding.

Learn more about MIG welding at Baker’s Gas and Welding.


Related Products

Miller Millermatic 211


SKU: MIL907614

Miller Spoolmate 100


SKU: MIL300371

Miller Spoolmate 150


SKU: MIL301272

Tweco 160A Spool Gun


SKU: TWE1027-1397


4 thoughts on “How to MIG Weld Aluminum”

  1. Richard Sivertson says:

    I have a miller 212 and spool gun.When I pull the trigger the wire feeds 1 inch the machine shuts off and over temp light comes on..The steel wire gun works fine on iron But the spool gun for aliminium has me shut down.Any advice would be greatful

    1. Adrian says:

      Are you using reverse polarity or DCEP?

  2. LW School says:

    I just bought a welder from Lincoln Electric, is impressive as well.

  3. Damian Ramirez says:

    I myself am a professional welder and I love reading blogs about welding and the related works done. Thanks for this post. It helped me a lot to choose the right one for my own use.

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