Whew! You already know that Aluminum’s expensive.
And the biggest problem you’ll have when your welding Aluminum?
Dirty metal.
And it doesn’t matter if you’re MIG Welding.
Or you’re TIG welding Aluminum?
You’ll be grateful when you’ve the right wire brush for Aluminum in your tool box.
You’ll find the right scratch brush to use on your Aluminum.
When you use it. And how you use your Aluminum wire brush for the best clean.
Can You Wire Brush Aluminum?
Yes.
Can you use a wire brush on Aluminum? Is one of the first question questions asked by a welder handling Aluminum.
You use a wire scratch brush.
But because of Aluminum’s special properties. You need to take care which wire brush you use.
Wire Scratch Brushes Not To Use On Aluminum
Wire Scratch Brushes You Don’t Use On Aluminum
You never use a scratch brush made from mild carbon steel because:
1. It won’t break through the Aluminum Oxide layer.
2. Not only that you’ll embed flecks of steel into your Aluminum. Result. A disastrous weld experience and porosity in your weld.
3. Plus those flecks of mild steel will rust over time. Your outcome? Rust all over and embedded in your beautiful Aluminum.
Don’t Use A Brass Scratch Brush On Aluminum Either
Because:
1. A brass brush will also struggle getting through the Aluminum Oxide layer.
2. You don’t want to risk leaving minute flecks of brass on your Aluminum, to cause you huge problems when you weld.
3. Not only that but Aluminum, brass and salt water is a combination to avoid.
And you could accidentally end up with that mix.
Here’s a for instance.
Your Aluminum part, remember that part you used a brass scratch brush on. That part covered in minute specks of brass. Is now outside.
Say, in a marine environment. Or during the winter when salting of the roads splashes salt water up onto your Aluminum part.
The brass and the Aluminum act like different ends of a battery in contact with salt water. Causing your Aluminum to very slowly dissolve …
What Type Of Wire Brush Is Used For Aluminum
A scratch brush with stainless steel bristles is the wire brush of choice on Aluminum.
Because a stainless steel brush is abrasive. Enough to scratch through the covering of Aluminum oxide. And get that Oxide off your Aluminum.
Yet the stainless steel brush keeps its bristles intact. And you’ll have no tiny specs of stainless steel on. Or in your soft Aluminum.
Finding The Best Wire Brush For Aluminum
Now you know what type of brush you need. You now need to source a good quality brush.
You’ll find below the top three best wire scratch brushes for use on your Aluminum project.
*Disclosure: This document contains affiliate links. And at no extra cost to you this site earns a commission through these links should you decide to buy.
1. Top Stainless Steel Scratch Brush For Aluminum
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The Forney Aluminum scratch brush has a wooden handle. And stainless steel wire bristles in 4 x 16 rows.
You’ll find it’s 10 and a 1/4 inch long.
Reasons To Buy
Forney is a great name in the welding industry and this brush lives up to the Forney build quality. For the price it’s a much better quality scratch brush on Aluminum than you’d expect.
2. Runner up
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You’ll find the Osborn International has a wooden handle. It’s a stainless steel scratch brush with a 6 inch bristle area.
You’ll find it’s 13 and 11/16 inches long.
Great if you’ve got large hands.
Reasons To Buy
You’ll find this heavy duty stainless steel scratch brush ideal for Aluminum. The handle is hard wood and it’s kiln dried. And that keeps its handle looking better longer.
You’ll find the Osborn wire brush stands up to hard use. And continues to look like it’s new even after a lot hard work.
3. Also Great
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Lincoln Electric is another great name in the welding industry. And is known for producing great products.
Reasons To Buy
You’ll find the Lincoln’s stainless steel scratch brush has a narrow profile. Ideal for those tight spaces on your Aluminum project.
This wire brush’s wooden handle is heat treated. And that mean’s it’ll last a long time and resist mold. Its stainless steel bristles are designed to stay put and last.
You’ll get a wire brush that’s 7 and 3/4 inches long and 0.45 inches wide.
Tell Me. What Are The Special Properties Of Aluminum?
Glad you asked.
Aluminum is a relatively light and soft metal. It’s much softer than mild carbon steel. And your Aluminum has a lower melting point than steel.
So what?
That means when you weld, it’s easy to burn through. And put holes in your Aluminum.
It’s shiny, attractive looking. And is often used where strength, lightness and resistance to rust is an advantage.
And this often means the outside of buildings, on boats and for railings. These are just a few of the many places you see it used.
Yet Aluminum is reactive with air. So reactive that within the shortest time a coating of Aluminum Oxide builds up on the surface.
Why is that important?
Aluminum Oxide has a different melting point to the virgin Aluminum.
And you’ll get a poor weld welding though it.
And that means before you weld repair. Or weld fresh from the factory Aluminum you get the Aluminum Oxide off first.
Plus any water vapor, moisture, or just plain dirt will mark the surface. And turn your pretty Aluminum dull grey.
Why Do You Use A Wire Brush On Aluminum?
You’ll find a wire brush an important part of cleaning Aluminum.
It’s not the only part of getting Aluminum clean enough to weld well. Though it’s a key step in the process.
You’ll use your wire brush. Often called a wire scratch brush. To take the final layer of Aluminum oxide off your sheet metal.
Aluminum oxide melts at a much higher temperature than the Aluminum below it. When you’re MIG or TIG welding and you don’t remove your Aluminum Oxide layer. You’ll first have problems striking your arc.
And an inconsistent melting of your Aluminum underneath.
Dirty Aluminum means a poor weld. Along with porosity (small holes within your weld). You’ll have black specs and lots of soot.
When To Use Your Stainless Steel Wire Scratch Brush
Taking your stainless steel bristle brush to your Aluminum. Is not the first step in cleaning your Aluminum.
Metal exposed to the elements. Out in the rain, and sun will look grey.
Along with more obvious watermarks, dirt and grime.
That’s dirty Aluminum.
And when you touch your Aluminum. You transfer the natural oils from your hands onto your Aluminum.
It’s not obvious you. But even fresh Aluminum from your supplier will have a layer of oil or grease on it. They use the oil to cut down the surface Aluminum Oxide build up. But it doesn’t prevent it all together.
So even Aluminum fresh and shiny straight from your supplier. Needs a clean before you take your scratch brush. Or your welder to it.
You first clean your Aluminum By:
1. Use Acetone.
And a clean lint free cloth to wipe off oil and grease on the surface. Not your wire brush for Aluminum.
Using your scratch brush at this stage will only smear the oil and grease around.
Potentially burying it deeper into the surface and trapping it.
Acetone is perfectly safe for cleaning oil and grease off your Aluminum. In fact it’s one of the best solvents to use.
Acetone does no harm to the Aluminum at all, and best of all it evaporates quickly. Meaning there’s no residue to cause problems with your weld.
If you don’t have access to 100% Acetone. Then you can use a strong soap solution. But you’ll need to wash it off your Aluminum and dry thoroughly.
2. Use A Grinder And A Flap Disc.
You use a flap disc made for Aluminum. Your flap disc will remove the dirt, watermarks and Aluminum oxide.
It’s important to use a flap disc for Aluminum on Aluminum. Because other flap discs will heat the surface of your Aluminum. And polish your Aluminum oxide but not remove it at all.
3. Then Use Your Wire Brush For Your Aluminum
Use as your final pass across your Aluminum welding surface. And your scratch brush will get rid of the last Aluminum oxide.
Then you wipe with a fresh lint free cloth (not the same one you used earlier to remove the grease). To wipe away the last of the Aluminum oxide.
4. Now You’re Ready To Weld.
You’ll have clean, well prepared Aluminum.
But keep in mind that Aluminum is highly reactive with air. Leave your bare Aluminum for hours in even the best workshop conditions. And you’ll get a nice new layer of Aluminum Oxide.
Not to mention dust from your home workshop settling on the surface.
If you’re not TIG or MIG welding straight away. But you’ve cleaned your metal well. You’ll get away with using just your wire brush to remove the small Aluminum oxide build up of a few hours.
When To Use A Wire Brush For Aluminum Welding
1. You use your wire brush just before you weld. To remove the last of the Aluminum Oxide off the surface of your Aluminum.
2. Use between your weld passes when filling a beveled weld joint. Any Aluminum Oxide on the surface. As well as any contaminants you scratch off with your wire brush before your next weld pass.
3. After you’ve welded. To remove any soot, black specs and contamination that welding has surfaced..
How To Wire Brush Aluminum
To effectively use your wire scratch brush on Aluminum. Scratch your brush in one direction. Then the other.
Thing to watch.
1. First don’t brush too hard. You want to remove the Aluminum oxide. But not embed any surface contaminants into your soft Aluminum.
2. Brush up and down. From top to bottom, moving across the surface you want clean.
3. Then brush left to right.
4. Finally take a clean lint free cloth and wipe. Then you are ready to weld. If you want a spotless weld then you can follow your scratch brush clean with Scotchbrite.
Final Aluminum Wire Brush Tips
1. Only use a stainless steel wire scratch brush on Aluminum
2. Keep your stainless steel scratch brush you use on Aluminum only for Aluminum.
Clearly mark your brush with a sharpie so there is no doubt.
Aluminum is so easily contaminated by other metals. You’ll only regret swapping your scratch brush back forth as soon as you have a poor, porous TIG weld.
3. Don’t press too hard on your stainless steel bristles.
4. Choose wooden handles that are heat treated. Because mold won’t affect the brush and it’ll last you a long time.
5. Pick a wire brush with quality bristles. You want the bristles to stay on the brush not all over your Aluminum.
6. You likely need different widths of scratch brushes. Say a narrow brush to get into the small corner space of a fillet weld. And a wider Aluminum wire brush for scratching larger areas.
7. Pick a brush length to fit the size of your hands. A brush that fits your hands is much easier for you to use.
What To Do Next
Did you find this article “Find the Right Wire Brush for Aluminum (and How to Use It)” useful?
Feel free to explore my other articles on the site about working with and welding Aluminum.
Best Wire For MIG Welding Aluminum
Scrambling Desperately For Flux Core Aluminum Welding Wire
