Can You Weld Aluminum With Flux Core – Is It Possible (Step By Step Instruction)

Are you thinking about welding aluminum with flux core arc welding process?

Do you think it is possible even if you do not know anybody who has done it? What do you need to do this except flux core welder machine?

There is no need to worry, because I am going to lay out all the facts about this tricky process. But it is not easy, mind you.

So, before you get your tools and gear, read this article to gain more information.

Can You Weld Aluminum with Flux Core
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What is Flux Core Welding and How It Works?

Flux Core Arc Welding (FCAW) or dual shield welding is quite similar to the Metal Active Gas (MAG) welding process. It uses continuous wire-fed electrodes at a constant voltage supply to mingle metals at intersections.

The filler wire in FCAW is usually vacant and filled with flux. This flux covers and shields the weld pool so that the gas does not have to do it. Due to this, the weld cools faster than usual and becomes more secure.

FCAW has overcome the multitude of restrictions that were present with MMA welding by using continuous wire-fed electrodes. However, it does produce a high amount of harmful fumes that are detrimental to the welder and the environment. 

Can You Weld Aluminum with Flux Core?

The answer is no.

According to experts, this is a tricky process. You may be able to run an aluminum wire through the flux core welding gun provided you have a slick liner and you run the gun straight over the wire. However, you may also think about using a spool gun for this.

To weld aluminum with flux core, you need a shielding gas. Even if you manage to run a flux core over the metal, the aluminum may oxide and you would need to remove that.

Watch the following video to know why flux core weld aluminum is a bad idea.

How to Weld Aluminum with Flux Core (Step-by-Step Guide)

If you insist to weld aluminum with flux core welding process you need to follow the guide bellow. Though you will not get best result, it will work.

Quick speed action and high deposition rates make flux core welding one of the most popular techniques to weld aluminum. You have to use a push-pull or spool gun to get the wire feeding going.

What You Will Need

  • An output of 35 to 88 amperes
  • A 20 amperes outlet to support 115 volts
  • A push-pull or spool welding gun
  • Pliers
  • Wire brush
  • Chipping hammer
  • Magnets
  • Clamps
  • Fume extractor
  • Tape measure or metal ruler
  • Grinder with wire wheels
  • Personal Protection Equipment (PPE) such as eye, ears, nose, mouth, hands, and feet protection
  • Step 1: Some Basic Preparations

There is always a chance of aluminum becoming porous, so the filler rod and base material need to be clean. You must also have good shielding gas coverage and keep the environment free of moisture.

You can either use carbon dioxide as a shielding gas for flux core welding. Even the flux core itself can provide all the slagging materials and shielding gas. Additionally, the sparks produced from FCAW can catch fire easily, so keep any flammable items away from the vicinity.

Basically, clean the metal as well as the space of work with the grinder and wire brush before getting started. Getting rid of paint or rust can greatly improve the quality of your welding. Use the clamps to secure the metal properly.

  • Step 2: Size Up the Metal

Once all the basic preps are done, it is time to shape up the metal according to the project at hand. Use the clamp to hold it down, measure with the metal ruler, and cut off what you do not need.

For your information, you do not want to weld loose materials. They will just add to your burdens later on. Therefore, check your piece twice before getting the welding gun.

  • Step 3: Adjust the Settings and Run the Welder

Set the welding gun according to the thickness of the welding metal. The higher the thickness, the higher the wire speed and voltage of the gun. A trick is to test the machine on a small piece of scrap before running it over the real piece.

When you pull the trigger of the welding gun, pay attention to where the deposits are made over the metal. All the sides must be equally welded for even distribution and perfection.

Also, clean up the area immediately for continuous improvement. You will be able to notice mistakes when the place is cleaner.

Consistency is key here. You should not expect your first few welds to come out like a masterpiece because that is unrealistic. Pay attention to the electrical stick out, travel speed, and torch angle as they will greatly affect the quality of your weld.

  • Step 4: Cleaning Up the Space Again

Do not be disheartened by all the clean-ups you have to do. It plays a big role in defining the perfection of your work. The slag and spatter left behind by your welder needs to be cleared with the wire brush and chipping hammer.

Clamp and re-clamp your locking pliers to grind the outer layers of the weld. If you can do it right, the final result becomes seamless with no cracks and holes.

Once all that is done, and you are happy with what you have manufactured, put everything back into place. Take care of all the tools and clean them if necessary before storing them.

What to Consider While Welding Aluminum with Flux Core

Welding aluminum surely is not an easy task, as you can guess from the step-by-step guide illustrated above. There are a lot of preparations that go in the planning. In fact, there is more to consider when welding this metal with flux core.

Work Angle

According to the American Welding Society, there are four welding positions a welder can apply to flux core weld on aluminum.

They are:

The signs 1 on the welder indicate that a flat position is suitable for proper welding (1F or 1G), 2 is horizontal (2F or 2G), 3 is vertical (3F or 3G), and 4 is overhead (4F or 4G).
Flat position is usually done on the upper surface of the joint. The horizontal welding can be conducted on a vertical plane, and the upper area of the horizontal plane of the metal.
On a further note, vertical position is suitable for vertical welding, and the overhead work angle means that you can weld from the underside of the joint.

Wire Selection

There is no flux core wire available for aluminum, unfortunately. You can either get something made of solid aluminum or flux core steel wire. But a shielding gas is compulsory.

However, you can use flux core wire to weld aluminum, which is demonstrated in following video.

Gas Selection

For aluminum, you must choose a shielding gas from carbon dioxide, helium, and argon. You can combine the latter two for welding, but you can also use them separately.

Safety Issues to Consider

  • Remove all flammable items from the vicinity beforehand to avoid things catching fire from the flux core welding.
  • Wear a PPE suit to protect yourself from the sparks formed during the welding process.
  • Research and train yourself about flux core welding with aluminum before you even think about experimenting.

Frequently Asked Questions

Here are a few questions you may be pondering about using flux core arc welding on aluminum. Scroll down to get a little more clarity about this amazing process.

1. What Metals Can You Weld with Flux Core?

Flux core welding can be done on various kinds of metal, such as stainless steel, steel alloys, and nickel alloys. You may want to choose ferrous metals that require high speed deposition rates to weld.

2. What Gas Do You Weld Aluminum With?

Two main gasses are used to weld aluminum. They are argon and helium. They are used either separately or combined for the perfect welding process. When it comes to aluminum, which is a non-ferrous metal, you need a 100 per cent shielding gas for the right weld

Last Words

Welding aluminum with flux core may be a little more challenging than other typical welding processes. Being a non-ferrous metal, welding aluminum requires the right amount of pure shielding gas, such as argon, helium, or carbon dioxide.

Oxidation is possible after welding, which you need to remove eventually. Also, anything flammable and dangerous must be eliminated from the vicinity to ensure your safety.

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