Can you paint over aluminum? Yes, you can paint over aluminum, but the paint may not stick without some extra work.
Before painting, you need to sand the aluminum and apply a primer.
You can then paint the surface with products that are specially formulated for use on metal.
How to Paint Aluminum Surfaces
Aluminum is lightweight, durable, and affordable, making it a common metal for a wide range of items.
From furniture and cabinet hardware to appliances and home décor, aluminum is found everywhere. It may also eventually rust, crack, or show signs of wear.
If you want to update the look of an aluminum object, use the following steps:
- Gather supplies
- Clean the aluminum
- Repair cracks and rust
- Sand the aluminum
- Apply a primer to the surface
- Paint the aluminum
- Use a sealer to protect the paint
Painting aluminum also requires an adequate workspace. The materials that you use may release harmful particles into the air, requiring you to paint aluminum in a well-ventilated space.
If possible, complete your paint project outdoors. If you need to complete it indoors, use fans or open windows to help with ventilation.
Some projects may also require you to disassemble parts. For example, if you want to paint aluminum cabinet hardware, unscrew the hardware from the cabinets.
1. Gather Supplies
What do you need to paint aluminum? You’ll need paint, primer, and a few other supplies:
- Brushes
- Paint roller
- Paint tray
- Cleaning rags and soap
- Wire brush
- Degreaser
- Liquid metal filler or welding putty
- Sandpaper
- Clear sealant
The brushes that you use depend on the type of object that you want to paint and the type of painting. If you’re trying to paint small details, you should purchase a set of art brushes in varying sizes.
Typically, 2.5-inch to 4-inch brushes are used for painting large surfaces, such as walls and ceilings. If you need to paint a large aluminum surface, consider using paint rollers.
You’ll also need soap and a degreaser to thoroughly clean the aluminum. Liquid metal filler or welding putty is necessary for repairing any damage. Clear sealant is an optional purchase that can help protect your paint from chipping.
Sandpaper is the most essential item, after paint and primer. You need coarse sandpaper (80-grit to 100-grit) and fine-grit sandpaper (400-grit to 600-grit).
When shopping for paint and primer, look for products that are formulated for use on metal. The paint contains extra chemicals that increase its ability to bond to metal surfaces.
Some primers designed for use on metal are called “self-etching primers.” Self-etching primer micro-etches the surface of the aluminum for better bonding.
Use latex or acrylic paint. If you’re planning on painting outdoor furniture or hardware, use paint designed for exterior use.
2. Clean the Aluminum
Dirt, grease, and debris may create problems later if you don’t clean the aluminum before painting. Fill a bucket with warm, soapy water.
If the object is small enough, place it inside the bucket. Otherwise, use a rag to wipe the surface of the aluminum.
Dish soap should help remove dirt and grease. For tougher jobs, you may need a degreaser. Degreasers can be applied using an old rag.
If the object has existing paint in areas that you want to paint over, attempt to remove the paint.
Use acetone or a paint remover to strip away the paint. Using a paint remover typically requires the use of an after-wash to remove residue.
After using a degreaser or paint remover, clean the entire surface with soapy water. Dry the aluminum with a clean rag or allow it to air dry.
3. Repair Cracks and Rust
Fix any imperfections on the surface. You may notice cracks, gouges, or rust. The damage will remain visible if you simply paint over it.
To remove rust:
- Add a small amount of degreaser to a container of warm water
- Dip the wire brush in the solution and scrub the rust away
- Wash the surface with clean water and dry with a clean rag
Use a liquid metal filler or welding putty to repair the damage. You may also notice new cracks or gouges after scraping away the rust.
Use the instructions that come with the filler or putty. You may need to wear latex gloves and use a putty knife to smooth out the material.
4. Sand the Aluminum
Sanding is one of the most important steps for painting aluminum. Without sanding, the paint may not adhere to smooth metal surfaces.
Use 80- to 100-grit sandpaper to rough up the surface of the aluminum. The coarse sandpaper may leave scratch marks on the surface. Use 400-grit or 600-grit sandpaper to polish the surface and remove scratches.
Use a circular motion when sanding, especially when using fine-grit sandpaper. Using a circular motion helps create a smoother finish. By the time you finish sanding, the aluminum should be dull and free of scratches.
Rinse the aluminum again using clean water. Allow the aluminum to dry, or use a rag to wipe it dry.
5. Apply a Primer to the Surface
Use a primer to give the paint a better surface. Make sure that you use a primer that is made for metal, such as a self-etching primer.
Before brushing or spraying the primer, cover any areas that you want to protect from paint. Use painter’s tape and plastic tarps or sheets to shield other objects.
You can apply the primer using a brush, spray gun, or spray paint. Spray guns and spray paint make it easier to apply an even coat.
If you decide to use a brush, pay attention to drip marks. Smooth out drips immediately using your brush.
If you use a spray gun or spray paint, stand about 12 inches away. Start with your hand to the right of the aluminum and spray in a sweeping motion toward the left. Move your hand beyond the aluminum in both directions to evenly cover the surface.
After priming the surface, allow the primer to dry. Sand the surface using coarse and fine-grit sandpaper.
6. Paint the Aluminum
Paint the aluminum using brushes or rollers. Brushes are more likely to leave marks in the paint, while rollers tend to create a smooth finish. However, brushes are necessary when painting curved surfaces.
You can also use a spray gun or spray paint. However, avoid applying too much paint. Use swift passes at a distance of at least 12 inches.
You may need to apply two to three coats. Always allow a coat to dry for several hours before adding another coat.
7. Use a Sealer to Protect the Paint
The last step is to add a clear coat of acrylic or latex sealer. The easiest solution is to buy the sealer in a spray can. Apply a light coat and allow it to dry overnight.
The sealer keeps the paint from chipping and protects against scratches. If you want the surface to appear shiny, use a sealer with a gloss finish. Use a flat-finish, clear coat for a duller look.
So, Can You Paint Over Aluminum?
Paint doesn’t adhere well to smooth, nonporous surfaces, such as aluminum.
Clean and sand the aluminum before applying a primer. Lightly sand the primer before painting with water-based paint, such as latex or acrylic paint.