How to Weld Aluminum with MIG Welder

Our team independently selects, reviews, and identifies the best products. We may earn affiliate commissions on purchases made from links on this page. Read about our links here.

Welding is a fabrication process that involves joining two pieces of metal using heat and moulding them to various shapes to come up with the final items.

As that’s the case, this article will educate you on how to weld aluminum with MIG welder. In full, it’s a Metal Inert Gas welder. Thanks to modern technology.

MIG welding aluminum can be a bit challenging if you’re used to common steel welding. This is because aluminum, in its pure form, is soft compared to steel. Due to the softness, many welders face challenges dealing with the metal.

In general welding, the parts joined together are called the parent materials, while the parts that help them bond are known as consumable materials.

Additionally, consumable material should be of similar composition to the parent material.

With this basic welding knowledge, specifically metal inert gas welding, you don’t have to purchase some household items.

All you do is buy relevant MIG welding machines and components, purchase some aluminum materials and make your items at home.

Luckily, you can even MIG weld aluminum to manufacture some simple home items that you may sell and earn some income. Examples are;

  • Tables
  • Aluminum home shelves
  • Lamps
  • Picture frames
  • A simple boat.

Before you would learn how to weld and kick off your aluminum products selling business, it’s good to learn more about MIG welding and the aluminum metal composition.

Understanding Mig Welding and Aluminum Metal’s Composition

How to Weld Aluminum with MIG Welder

a) MIG Welding

MIG welding is one of the several welding methods that use electricity to melt and join metal pieces.

Since its invention in the early 20th century, MIG welding has been widely used due to its easy-to-learn and practice methods and welding speed.

MIG welding method uses high electric voltage to create an electrical arc. The arc is usually made of electrode wire (the positive anode), and the parent metal or the working piece is used as a negative cathode.

The electrical anode wire is melted to form a consumable material between the two aluminum pieces during welding. And as a result, it forms a strong bond between the two after cooling.

In modern MIG welding machines, the electrode wire used as a consumable material is fed in the same line with the shielding gas in the MIG welding machine gun.

Luckily, you have one handheld gun supplying all the required materials.

Related Read: Aluminum storage box for trucks

How to Weld Aluminum with MIG Welder

b) The Aluminum Metal

On the other hand, aluminum is a widely used lightweight metal. Due to its weight, many automobile and aircraft manufacturers use it to make bodies.

Additionally, it can make the best transmission cables, engine cylinder heads, radiators, and heat exchangers.

Aluminum is a good electricity conductor due to its softness, flexibility, and corrosion resistance. Unfortunately, it is lighter and thinner than steel.

For this reason, it needs careful handling while welding. When passing heat, note it has a low melting point, which may cause holes to develop on the working piece destroying the quality of your final item.

However, here are summarized key points to note before dealing with aluminum metal;

  • It has higher conductivity than steel.
  • It has a lower melting point.
  • It’s more reactive to oxidation.
  • Oxidation layer shields it from corrosion.
  • Oxidation layer downgrades its welding ability.

Read: Best tool for cutting sheet metal

How to Weld Aluminum with MIG Welder

How to Weld Aluminum with Mig Welder

You need several protective gears and other equipment to weld your aluminum with a MIG welder. They are;

  •  Welding helmet – it protects your head from sparks.
  •  Safety glasses – they protect your eyes from sparks and debris that may fly from the work piece.
  •  Welding jacket and boots – protect the whole body from sparks and debris. You wouldn’t want to mess with your clothes.
  •  Leather gloves – they protect your hands when you touch the hot workpiece surface.
  • Ceramic tile – It will hold the aluminum pieces into place for easy welding. This material doesn’t disrupt your welding activity.
  •  Brass brush – It’s used to clean the aluminum oxidation layer. You can use sandpaper as an option.

The procedure;

1Gather your aluminum workpieces
2Using the brass brush or the sandpaper, clean the oxidation layer on the aluminum workpiece surface.
3Place the two-parent materials on the ceramic tile and grip them firmly for easy welding
4Choose the best shielding gas (Argon gas is proven best for aluminum). A shielding gas protects the melted weld pool from atmospheric gases like oxygen, hydrogen, or nitrogen. If allowed to react, it can cause the material to develop holes or high spattering.
5Set the heat to around 730 degrees Fahrenheit (the aluminum melting point) and weld the materials.
6Shape the material to develop your desired frames and ensure you move the gum fast to avoid porosity on the parent materials.
7After completing, allow the materials to cool.
How to Weld Aluminum with MIG Welder

While working with your aluminum materials, there are four common mistakes with the electric wire that may occur. Note them and their solutions as described below;

  • Incomplete penetration – increase the wire feed but don’t allow it to protrude much from the gun.
  • Excessive penetration– reduce the gap between the two working pieces.
  • Incomplete fusion – prevent the wire from getting in front of the weld pool.
  • Whiskers development – reduce the size of the weld pool and check the wire not to protrude much from the gun.

Mig Welding Pros

  • Continuous movement of electrode wire fastens the process.
  • It can join different metal types.
  • It welds in all positions (horizontally, vertically, or flat).
  • Fewer waste parts compared to torch welding.

Mig Welding Cons

  • Works best with only medium-thick metals.
  • Because of inert and shielding gas, it’s less portable.
  • Higher investments and maintenance costs
  • Outdoor welding can be difficult due to wind blowing the shielding gas.

Read Also: Must have power tool accessories

How to Weld Aluminum with MIG Welder

FAQs on Welding Aluminum

Can I Weld Aluminum with My Wire Feed Welder?

Welding aluminum with a wire feed welder is possible. However, note that aluminum is highly conductive, and welding with lower voltages may cause even heat distribution. This can be the hardest experience during welding.

Can You Weld Aluminum With Steel Wire?

While various metals can bond with aluminum through mechanical fastening or adhesive bonding, steel is different. You can successfully weld aluminum and steel with a special technique to avoid brittle inter-metallic compounds from forming by isolating steel from the molten aluminum when performing the process.

What Kind of a Wire Do You Use to Weld Aluminum?

4043 is widely used for aluminum MIG welding, but you can also choose 5356 wires.  5356 can weld various aluminum types like 3000, 4000, 5000, and 6000. However, when using 5356, note it melts faster, requiring a faster speed. 4043 is proven best for home welding. If you have basic knowledge of how to weld aluminum with a MIG welder, nothing can stop you. Go on and make your income. 

Discover: Commercial shop vac