How To MIG Weld Aluminum Without a Spool Gun

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Welding aluminum can be a complex process and one that requires knowledge and experience to do well. Common aluminum is a very soft metal compared to others, such as steel, and it also has a high melting point, requiring max voltage. Despite being a relatively soft metal, welding aluminum without a spool gun is possible.

The most common methods include the following:

  • MIG Welding
  • TIG Welding
  • Torch or Argon Co2 Welding

While all these methods may work well, MIG welding holds the top position, and in this article, we will explore this method in more detail.

Is a spool gun necessary for MIG welding aluminum?

The short answer is no. Spool guns are mainly used for welding aluminum because the wires used to feed the electrode tend to become tangled or stuck due to their flexible nature and become more likely to happen in most machines when placed far away.

When welding and wire get stuck while being fed during the welding process, it’s known as bird nesting. Therefore, spool guns are used to avoid this from happening, as the spool of aluminum placed along with the gun reduces the length that the soft wire needs to travel to reach the electrode tip.

How to MIG weld without a spool gun

In simple terms, by not using a spool gun, the welder will need to get the aluminum wire fed through the electrode tip of the MIG gun. To do this, you will need to place the aluminum spool inside the weld the same way you would for other metals. The main risk in doing so is that when running aluminum wires through the gun, small aluminum wire pieces may fall off and contaminate the welding steel and cause aluminum wire feed issues.

When welding aluminum, you should ensure that you’re using the proper gas for aluminum. The most suitable is pure argon or an argon and helium mix. You should also ensure that you set your welder properly and prepare the surface you’ll be working on ahead of time. The thickness of the aluminum should help you determine the setting you will need for power and gas.

A buildup of aluminum oxide is possible; therefore, it would be best if you took care to remove the aluminum oxide, as it may cause poor welds. When using a mild steel wire brush, make sure that the brush that you’re using has only been used with aluminum to clean it. Alternatively, opt for an aluminum wire brush.

MIG welders are a specialty tool. Like most specialty tools, if you want to do high-quality work, it’s always advisable to spend a little extra on a class welder and suitable hoses to reduce the stress on the wire.

Tips or MIG welding aluminum without a spool gun

  • Test your setup – Once you’re all set up and before you start welding your actual work piece, try a few test pieces to ensure that the feed is working as it should and to help you get comfortable. If you’re new to welding soft metals, the process can be fairly tricky and will take a while to master. Each test will allow you to assess the results and determine how close you are to achieving the desired results.
  • Keep an eye on the hose – During the tests, if you encounter bird nests, the first remedy you could try is to increase the feed distance so that the hose is as straight as possible. This will help ensure that there is ample space for the wire inside the hose to remain kink-free and should improve any uneven feeding.
  • Tension and resistance – Ensuring that the resistance on the wire is kept at a suitable level is a key factor for a smooth welding process. If you notice bird nests or feel high levels of resistance, you can adjust the tension and feed speed to a lower level. Lowering these levels will help remove some of the resistance on the wire. Once you find the optimal speed of feeding the wire, try to maintain the same level throughout the entire project and take intervals in between welds.
  • Remain vigilant – Due to its softer nature, when working with aluminum wire, you need to be confident with the welder settings that you’re using. Coiled steel and aluminum wire are extremely different types of metals and require different voltage settings that are conducive to each. Too much heat or incorrect wire speed can cost you a good weld and mess up an entire project. Do not make the mistake of using old settings from a previous steel-based project on an aluminum one.
  • Choose a good quality MIG welder – When it comes to welding, choosing a high-quality and well-tested product makes all the difference. The Lincoln Electric’s 90 Amp FC90 is an excellent value-for-money option for MIG welding only, while the Tooliom 200-amp machine 3 in 1 is a slightly more expensive option but allows for more versatility. While the basic 90-100 amp welder should work fine, the Lincoln MIG also comes in a 110V machine variation for larger projects.
MIG/MAG welding gun or Mig welding torch

Advantages of using a spool gun for MIG welding

Although aluminum welding without a spool gun is possible, it is still advised since it provides several benefits. This includes:

  • Speed – Spool guns are designed to reduce the complexities involved with MIG welding, such as reducing the time spent adjusting the length according to the wire diameter. This allows for a simpler process, less chance of interruption and adjustment, and ultimately a faster result.
  • Neatness – Spool guns offer significant stability and are one of the main reasons that they are recommended when MIG welding aluminum. A more stable arc with steel wire, rather than aluminum filler wire, helps ensure that the weld beads maintain a good profile and that the welding proceeds with minimal undercuts or spatter.
  • Convenience – When using a spool gun, you have the flexibility to change between steel and aluminum welding without difficulty. In addition, when the welder is far away, it can become difficult to make the aluminum MIG wire roll smoothly and feed into the gun; however, with a spool gun, this trouble is removed.
  • Cost-effective – The expense involved can also be reduced since the wire pulling will not require any additional setup. All you will need to do is remove and replace the spool when needed.

Disadvantages of using a spool gun for MIG welding

Here are some of the issues with aluminum welding without a spool of steel wire:

  • Size – One of the more obvious drawbacks is that spool guns are much bulkier than MIG guns and will make for a much larger size machine. The additional parts required to hold the spool of metal also make the gun heavier as well.
  • Poor Accessibility – The amount of aluminum wire available in a spool located inside the spool gun can be limited. This means that if you intend to do a lot of welding in one go, you will need to replace the spools regularly, which can be time-consuming, especially in larger-size machines.
  • Complicated setup – If you’ve ever used a spool gun in the past, you will know that it can be fairly tricky to work with. The additional setup of the spool component makes it more complicated than a MIG gun, and in some instances, the spool of steel wire may not be compatible. This is a key factor and is one of the main reasons many individuals choose to go with a MIG gun instead of a spool one.
  • Extra Maintenance – Spool guns possess several small parts throughout the gun, which often means that maintenance can become an issue over a longer period of use. Wear and tear is inevitable, and due to the number of parts included in a spool gun, there is a greater chance of breakage or a replacement of parts.

Other methods to weld aluminum

As mentioned earlier, in addition to MIG welding, there are two other ways that you can weld aluminum without a spool gun:

  1. TIG Welding – This is likely the more viable of the two methods. TIG welding will require you to feed the filler material with your hands, while your legs will also be required to control the pedal. TIG welding requires extra vigilance and can be time-consuming.
  2. Compared to MIG welding, TIG can be a lot trickier and will likely take longer to perfect since specific requirements are involved in welding different types of metals.
  3. Propane Torch Welding – Also known as argon gas welding or oxy-acetylene welding. This method requires using oxygen and acetylene gas for aluminum work, which comes in an argon tank and creates a very high temperature required for a smooth and perfect weld. When used on aluminum, argon tank welding can provide a great aesthetic look using only a gun with aluminum settings. Users should take note of storage requirements for cylinders of argon to ensure their safety.


MIG welding aluminum is entirely possible but does require some practice to master. While using a spool does provide significant advantages, the main one is that it reduces feed wire trouble; therefore, MIG welder users will need to focus on this element to learn. However, with a little bit of practice and patience, you should be able to learn the most effective process for success in creating good beads and an overall strong aluminum weld.

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