You’ve a great 90 Amp or 130 Amp flux core welder, that uses flux core welding wire.
But you’ve this little job to do. And it’s Aluminum.
You ask yourself. ‘Can you weld Aluminum with a flux core welder?’
And use flux core aluminum welding wire?’
Because you don’t want to buy a cylinder of Argon shielding gas.
What you really, really want is a spool of Aluminum flux core wire.
And you want it now.
So, can you flux core weld Aluminum?
You’ve searched online and it has led you here.
Your search for flux core Aluminum welding wire on Google will have shown you a bunch of adverts.
With welding wires that claim they are Aluminum flux core welding wires. Or say they are gasless aluminum MIG wires.
Others are reels of solid Aluminum MIG wire when you look up close. And you know your gasless flux core welder can’t use that.
Cause that stuff needs Argon gas.
You search and search. You start to question whether there is such a thing as flux core Aluminum welding wire?
In your quest some of the wires look tantalizingly like what you want.
But the stark truth is that none of them are ok for welding Aluminum with your flux core welder.
And when you do use that stuff then you’re going to need a new welder soon.
Because your best case is that the wires won’t weld at all. And your worst case is they stuff up your flux core welder.
And if you do use that stuff then you’re going to need .
As the best case is that the wires won’t weld at all. And in the worst case they stuff up your flux core welder.
That Unicorn … The Holy Grail Of MIG Welding Flux Core Aluminum Wire
Is flux core Aluminum welding wire a unicorn? That mythical creature searched and searched for.
The answer is Yes.
Gasless flux cored Aluminum wire for your flux core welder exists only in the imagination.
So why does the rumor of its existence raise its head every few years?
Interested in what flux core wire really is? Take a look at this article ‘What is Flux Core Wire’ And find out all about it.
The Truth About Aluminum Flux Core Wire
You’ll find that even when the welding wire says flux core in the ‘title’ a closer look reveals:
1. It’s solid Aluminum welding wire and the small print says Argon gas recommended.
Actually it’s more than recommended it’s crucial.
And what’s more you’ll need a MIG welder that uses shielding gas.
That means the wire is for MIG welding not gasless flux core welding at all. Or.
2. You’ll find it’s soldering wire.
Again a process that has nothing to do with MIG welding or flux core welding. Or.
3. That it’s Aluminum wire, flux core yes;
But the wire is for brazing machines. Brazing machines have an automatic wire feed.
That it’s really wire for use a furnace. A furnace where the air supply is tightly controlled.
Or for wire used in induction brazing.
And when it’s not either of those wires. It’s wire used with a propane gas torch or a torch that produces a flame.
All that means it isn’t MIG wire but brazing wire.
It’s not what you’re after.
Where Can You Find Flux Core Aluminum MIG Welding Wire For Sale?
And I get why you’re searching for this unicorn.
You’ve a $100-$300 flux core only welder because you wanted to get into welding. Because you had some small mild steel welding jobs to do.
Your budget didn’t stretch to a more expensive MIG with gas.
And now you’ve just this bit of Aluminum welding and you don’t want to pay someone else to weld it for you.
But there are good reasons why there’s still no sign of this unicorn.
No Flux Cored Aluminum Welding Wire On Sale
There’s a great article from The Fabricator.com by Frank Armao of Lincoln Electric on the subject. Frank Armao is a member of several relevant American Welding Society committees.
The article dates from 2013 and is still valid today.
The points he makes are;
1. No Standard For Flux Cored Aluminum Wire
You’ll find that the American Welding Society (AWS) has no standard for flux cored Aluminum wire.
Here’s a link to the standards page for you to double check if things change. It’s unlikely.
2. No Flux For Aluminum
The fact is, that the flux chemicals in common use for steel MIG welding don’t work for Aluminum.
Aluminum is too reactive with air.
And that means finding new shielding chemicals.
3. Failed Lab Tests
There were some laboratory tests of fluxes that worked for Aluminum.
But tests in a laboratory. And moving from lab tests to commercial products.
Well, they’re two very different things.
4. Flux Core Aluminum Wire Doesn’t Work In The Real World
The reason the process is difficult in the real world.
Is in the real world, outside of the laboratory. There’s much to control.
The Aluminum flux core wire storage. The flux covered Aluminum feeding well in a flux core welder.
Having the flux not only shield, but bring to the surface contaminants in the weld. Like normal flux core welding wire does.
A chemical shield that works as a flux for flux Aluminum welding is a huge problem.
Aluminum is just so reactive.
5. Corroding Aluminum Flux Shielding Chemicals
The shielding chemicals used in the lab experiments were corrosive.
Not exactly what you want for your weld.
They sucked up water from the air. This meant storage of your Aluminum flux cored welding wire was a problem.
Imagine yourself opening your Aluminum flux core welding wire. Then a few short minutes later you found your welding wire contaminated and useless. You’ll be far beyond upset.
And you’d need strict storage conditions for your flux core aluminum wire. Otherwise, your weld joint would be poor, porous and fail.
6. Environmental Disaster
On top of all that, the flux core chemicals that worked in the lab were a disaster to the environment.
And who wants that.
Here is a link to the article:
There’s no such thing as flux cored Aluminum welding wire for sale. And for good reasons it doesn’t exist.
So what options do you have for welding Aluminum?
Can You Use ‘Normal’ Flux Core Welding Wire To Weld Aluminum?
The short answer is no. You can’t use steel based flux core wire in your FCAW welder to weld Aluminum.
It just won’t work. And you won’t get the join you expected.
You may burn out your welder. The Amps needed to weld Aluminum is more than a basic 90 Amp or 130 Amp welder can generate.
The splatter produced would be mind blowing. It would clog up your contact tip and could even short out your welder.
And after that you’d have no weld or one that failed.
No point trying that one.
Welding Aluminum Without Gas? What Are Your Options?
The only method out there that possibly uses no gas at all is soldering.
But even in the various methods of soldering you’ll find a propane gas torch. It’s used to melt the solder material into and onto the joint.
There are limits to the use of a soldering iron to weld Aluminum. Because a soldering iron can’t generate enough heat. Well not enough to create a firm joint of any significant size.
The Aluminum joint needs to be extremely clean. As any contaminants can cause your solder not to stick. Particularly as Aluminum is so reactive with air.
But at least there’s no gas involved in this process if you decide to solder with a soldering iron.
Aluminum Soldering With A Torch
There’s a difference between soldering a joint with a flame torch and brazing.
In soldering, the solder – the filler material – melts at a lower temperature compared to brazing wire.
You heat your Aluminum base metal but you don’t melt it. The Aluminum solder flows into a small gap between the Aluminum joints.
Aluminum Flux Core Wire For Brazing
In brazing the Aluminum filler material melts at a higher temperature. But it’s important to understand that the joints are still heated up but not melted as in arc welding.
Flux core Aluminum welding wire for brazing is not designed for use in an electrical arc. Flux core welding uses an electrical arc.
Brazing uses a gas flamed welding torch. Not a MIG torch.
The joint has the flame of the welding torch held near. The aim is to heat the Aluminum enough so the flux core Aluminum wire for brazing melts. But not so much that the Aluminum base metal melts.
A brazed joint needs to be scrupulously clean. Particularly when you’re joining Aluminum.
When your weld joint is dirty, you can file off the dirt. The alternative is to clean with chemicals. Or use a flap disc for Aluminum.
You bring the Aluminum joints together.
And by close together I mean a gap of 0.0012 to 0.024 of an inch. This is so that you can get enough flow of the filler material into the gap to make the join. And also for joint strength.
Gasless Aluminum Welding Wire, Is There Such A Thing?
Outside of soldering with a soldering iron and for the reasons above no.
Aluminum needs gas to weld. Whether it’s in the brazing process where you use a torch and with flammable gas to heat the joint. Then flow the brazing Aluminum filler metal into the joint.
Or in MIG or for TIG welding where Argon gas protects the hot metal from the air.
Because of the reactive nature of hot Aluminum it’s all too easy to spoil your join with contaminants in the air.
MIG Or TIG Welding Aluminum
Both MIG and TIG welding uses electricity and Argon shielding gas to protect the joint from the air.
And MIG and TIG uses an electrical arc to melt the base metals and the filler material. So that they all merge and flow together and that forms your weld.
Welding Aluminum, Without Flux Core Wire
Your options are:
1. The Best And Easiest Option Is To Get Yourself A MIG Welder
Get yourself a welder that can feed Argon shielding gas and weld Aluminum. And a MIG welder that welds Aluminum.
And you’ll need a MIG welder with a spool gun attachment. Your spool gun will feed your soft Aluminum welding wire close to the joint.
2. Your Prettiest Option For Aluminum Welding
Is a TIG welder. A skilled TIG welder makes their Aluminum welds look like a lesson in art.
You TIG weld when the joint is visible. And it’s important to you that it looks great. TIG welding is a slower process than MIG welding. It uses Argon shielding gas and demands skill and practice. But I suspect that if you’re doing this search you’re no TIG welder.
Because you’d have TIG welded the repair already.
3. A MIG Welder Powerful Enough, Plus Your MIG Gun, Plus A Teflon liner
It’s possible. Just.
When you’ve no spool gun you could try it.
You’ll still need Argon gas to shield your weld from the air. A Teflon liner helps the wire to slide through the hose and up to the MIG gun.
Because it’s ultra smooth and you’ll get less friction on your soft Aluminum MIG wire.
To Feed The Aluminum MIG Wire;
- Lay out as flat and as level as possible the cable or hose to your MIG gun. That way you’ve the best feed of your Aluminum MIG wire you can get.
- Adjust the tension rollers of your MIG’s wire feed. You want tension on your wire. But not so hard to crush your wire.
- Change your MIG welder’s polarity to weld with Argon gas and solid Aluminum wire. And it’s possible.
YouTube Video MIG Welding Without A Spool Gun
This 15 minute video takes you through the issues, and some of the solutions. Unfortunately it doesn’t show you a successful weld but it does show you what can happen and often does.
Tips for MIG Welding Aluminum without a Spool Gun
Video Credit: Weld.com
Aluminum is a soft metal. You can end up bending the Aluminum inside the hose. Because you’re feeding from the wire feeder in your MIG welder. Through 10 foot of cable to the torch head.
A non existent or poor wire feed.
Second YouTube Video MIG Welding Aluminum Without A Spool Gun
This next video 7 minute video not only covers the issues, The video shows some welds. Yes, the video is a bit rough and ready. But does show you how you can get it done.
How to MIG Welding Aluminum without a Spool Gun
Video Credit: A21bravo
The welds aren’t pretty and will need grinding to smooth off but he got a weld.
4. When You’re Desperate And Have Aluminum Flux Rods
And a stick welder to hand.
Here’s a video from WeldingTipsandTricks. He compares using a stick welder or a TIG welder with Aluminum flux stick rods. If you find yourself in a tight spot and that is all you have to hand. …
Again, works, but it’s not pretty. And there are issues with the joint with some porosity stick welding.
But when you’re stuck and in a jam it’s a way through.
YouTube Video Stick Welding Aluminum
Here’s the complete just under 4 minute video to take a look at
Stick Welding Aluminum
Video credit: weldingtipsandtricks
What To Do Next
The Unicorn of flux core Aluminum welding wire doesn’t unfortunately exist.
Even when you want it now.
But you found here some of the options available for welding Aluminum.
Why not take a look at some of the other related articles on the site.
About Bill Byers
I started welding at 27 and now have over 20 years on the job experience. I MIG, TIG and flux core weld. Even done a bit of Blacksmithing in my time.
I enjoy helping novice welders find their feet.
In my spare time you’ll find me enjoying a game of football.
And on the odd weekend paying a round of golf badly. Just duck when you see a golf club in my hand.