How to Weld Aluminum With MIG Welder

MIG welding aluminum is known to be very difficult, especially when you compare it to welding mild steel. There are some factors that you should consider so that you can be sure that you are doing the right thing.

Aluminum Welding

The thing about aluminum welding is it can be very tricky to do. Aluminum is a soft and thin type of metal. It has a lot of uses. If you would see the metal products that are being sold, most of them will be made out of aluminum. The only thing is that they would require other alloys so that they can become stronger.

Since it is very soft, there is a considerable chance that it will become distorted. Working with it can be a bit tricky, but with the right tools and materials, it will not be too hard to do.

Some Tips to Start Aluminum Welding with MIG Welder

You cannot just start welding aluminum when you do not know much about using it. This is not one of the most natural metals to work with. You need as many details as possible so that the items that you will use will not be wasted.

These are some tips that you can remember:

  • Always keep the aluminum clean before using it for welding. The dirtier the aluminum is going to be, the less appealing the welds are also going to be. You may need to remove the lubricants that are present in the aluminum.

First, you need to decrease the aluminum, and then you can also do oxide cleaning. Doing these things will remove the impurities that may affect how clean the weld that you are going to make will be. Remember to clean with a wire brush that has been used only on aluminum.

  • Look at the thickness of the aluminum. If it is 14 gauge and more massive, then it can be welded with a MIG welder. If not, you may need to find other methods to weld aluminum. Thinner aluminum would require a more specific type of welding equipment.
  • Only use 100% argon shielding gas. This is a non-ferrous metal, which means that other types of gases may cause the welding process to fail.
  • Use the spray transfer process when you want to weld the aluminum properly. This will allow the molten metal droplets to go from one end of the electrode to what you are trying to weld. The efficiency of this process is very high. Just remember that it would need a lot of heat so that it can work properly.

If you are not yet too comfortable in using a lot of heat, you may need to practice first so that it will not go out of control when you are trying to weld the actual aluminum material.

  • The gun and wire feeding system that you are going to use will play a massive role in how effective the welding is going to be. You can use a spool gun to improve the feeding of the wire. This will also make welding aluminum so much easier to use. You would like something user-friendly, especially when you are doing it for the first time.
  • Consider the right filler material that will be used. It was mentioned earlier that aluminum would need a filler material to make sure that it will be stronger. Different filler metals are available. What you have to do is to make the right choice.

Some Welding Techniques You Can Do

Now that you have learned the right tips in preparation for welding aluminum with MIG welding, these are some techniques that will make the process easier for you:

  • You need to know the right angle that will help you weld properly. You can use the forehand technique, also known as the push technique, to make the welding easier. The tip and the nozzle should be directed towards where the metal is supposed to travel. If you would use the backhand technique, you will get dirty welds that will not look appealing at all.
  • The right distance is necessary so that the liquid metal will reach its target correctly. The contact tube should be recessed 1/8 inch inside the nozzle. If the tip is too close to the aluminum, the metal will melt. Make sure that you will not place it too close.
  • Large weave will not be too useful when you are welding aluminum. Only use this when it is essential. Otherwise, you can go for multiple pass straight beads.
  • The torch travel speed needs to be increased as you continue welding. The longer that you have to weld, the faster the torch travel speed is going to be. You need to be ready for this to avoid the chances of making mistakes.

Some Common Problems You May Face

Welding aluminum is not the easiest welding project that you can do, so you can expect that there will be some mistakes along the way. Melted aluminum can be quite common, especially if you place the nozzle too close to the metal. You can create shorter welds to fix this issue. There is also a need to reduce the gaps to save the project.

Another problem has dirty welds. Let us say that you were not able to clean your aluminum correctly. You can avoid this by increasing the voltage of the spray transfer.

Some people are welding aluminum for the first time that may choose the wrong settings while welding. This can easily be remedied by turning off the machine that you are using and creating the proper settings. Once you have adjusted it, then it is time to use the machine for welding again.


It may take some time and a lot of practice before you can weld aluminum with MIG properly. If you can do this once, you will also create your tips so that you can do it again. Who knows, you may become an expert at it that you will have no problems with doing it often.