Painting metal is more complicated than other surfaces because it gives a different result. Because of the rust factor that affects metals, you’ll only enjoy the finished look if you treat the rust correctly while painting it.
Do you want to upcycle that metal piece in your home, or is it a total restoration project? Painting is an excellent way to refresh the appearance of that metal. Preparation is critical in metal painting. We cannot emphasize this enough.
You must set aside time for this project because it requires patience and care. This article will show some tricks to help you take as little time as possible while producing excellent results. Prepare to paint some metal like a pro!
Types of Metals Susceptible to Rust
To begin, we want to consider the type of metal you have before painting over it so that you are not surprised by rust months later. Not all metals rust at the same rate or manner. When you have this information, you can take the necessary precautions.
Rust is caused by the formation of iron oxide when the iron is exposed to moisture and air. This means that the only metals that can rust are iron and alloys containing iron.
The iron’s thickness affects how the rust looks and comes off. The type of iron determines how rusted the iron piece is and how much preparation it requires before painting.
Steel also rusts, but just like we previously mentioned, this is because iron is one of its components. Stainless steel is the only steel that can resist rust.
On the other hand, metals like copper, brass, gold, and aluminum don’t rust like iron, although they also erode, and some form a patina.
It’s unlikely that anyone usually wants to spray over these sorts of metal except aluminum, though, except to hide their value. However, the painting preparation method will be slightly different because they do not have the same luster as iron.
Materials and Tools Required to Paint Metal
- Orbital sander
- 120-grit sandpaper
- Wire brush
- Mineral spirit
- Oil-based paint
- Paint sealant
- Rust neutralizer
- Disposable cloth
- Soap and water
- Nose mask
Safety Precautions in Metal Painting
There are some precautions to take when spray painting for your safety.
Minimize Inhaling Unhealthy Fumes
Finding a suitable aerated space is essential. You can try painting outside or in the garage. Painting outside keeps fumes from getting on surfaces and affecting others.
Wear gloves, goggles, and a nose mask to protect yourself from paint. This tip goes for when you’re sanding the metal too. You don’t want to breathe in metal pieces.
Protect the Environment
Place canvas material on the ground outside to prevent paint from staining your surroundings. A canvas material is preferable because it holds the paint better. It can still slip out if you use a newspaper or a drop cloth. It is also easier to remove the paint from the canvas.
Also, immediately wipe down all surfaces it comes into contact with after using the mineral spirit. You can then wash the cloth with soap and water to prevent someone from consuming mineral spirits-stained food.
Stay Away from Fire
You should avoid fire while dealing with aerosol cans and mineral spirits. Also, keep the mineral spirit, neutralizer, and sealant in a cool, dry place. Heat is dangerous for solvent-based products. Then, close it after use.
Read the Manufacturer’s Instructions
Always read the can for the manufacturer’s directions on how to use the products. For certain products, you’ll need to follow specific instructions. If not, the results will not be palatable.
How to Deal with Rust While Painting Metal
Rust in metalwork is unavoidable. You’ll either have to face it before you start painting because if it’s old, it probably already has some rusty spots, or after painting your paint job chips and ruins due to rust.
It is already too late for the first scenario, but there is still hope that the second one will not occur. How you handle the metal before and after painting will determine the second outcome.
We’ll go over how to treat the rust before painting on metal and what to do after painting if you want it to last a long time before rusting.
Before painting rusty metal, sand it down and remove as much rust as possible. There may also be peeling paint from the previous paint job, which you must address.
You’ll need 120-grit sandpaper to smooth out the peeled paint and rust. Hand sanding is an option, but it is very slow, so if you have an orbital sander, attach your sandpaper to it and use that instead.
After that, depending on the extent of the rust damage, you can go over it again with 220-grit sandpaper for a polished finish. Whatever product you apply to the surface afterward must not show any signs of peeling paint or rust.
If your metal piece is small enough or you don’t have an orbital sander, you can do it by hand. You can use a wire brush if you prefer to go the manual route.
These brushes come in various diameters and types, each serving a different purpose depending on the type of rust. Don’t worry if it seems like hard work; it’ll all be worth it.
The next thing to do is to use a rust neutralizer or converter. A rust converter contains a compound that reacts with the rust to form a layer that acts as a makeshift primer.
It means the converter will protect the surface before you even use your primer. You also get longer-lasting results because the metal will not rust for an extended period. For extra protection, use a rust-preventing primer to give that rust a run for its money.
Considering all the work you put into keeping rust down before painting, you would think there can’t be much more work to do, but there is. Although you are not technically doing this after, the paint you use is also essential to review.
Oil-based paint is your best bet when painting metal. This is because it has a strong hold on metal. There is also metal-specific paint, but this may be overkill. Once you’ve completed all of the prerequisites, the metal-specific paint is optional.
The final stroke to ensure a long-lasting effect is a sealant. You’ll need to apply one after you’ve painted your metal. Instead of reacting directly with the metal or rust, it reacts with the paint, forming a waterproof layer that prevents moisture from reaching the metal.
How to Paint Metal (Step-by-step Guide)
The steps involved in the painting are straightforward. Spray painting is the best method for painting metal, even small pieces. Aside from the apparent brushstrokes, you may require a more seamless, glossy finish than with a brush. Here are the steps for painting metal.
Step 1: Clean the Object Thoroughly
The first step in any painting project is thoroughly cleaning the surface with soap and warm water to remove dust and grime.
Spraying over filth is not a good idea because it increases the chances of the paint job getting ruined. A clean surface lets you properly grip whatever you apply to the metal without bumps or air bubbles.
After washing, ensure all parts are thoroughly dried by spreading them out in the sun or patting them dry with a cloth. There should be no smudges of wetness at all.
Step 2: Sand the Metal
Sanding the surfaces you want to paint can save you time and effort. Most materials will not hold paint well, and metal is no exception. You’ll need 120-grit sandpaper to roughen up your metal.
You don’t need to use too much force when sanding, especially if there is no rust on the surface. Simply scratch it lightly all over to remove the smoothness and luster.
Step 3: Use Mineral Spirit to clean
Wipe off the dust from sanding with a rag dipped in mineral spirit to get that metal dust off the surface. The solvent also cleans the surface by removing any remaining grease. The mineral spirit dries quickly and prepares your surface for the next step.
Pro Tip: Dispose of the rag properly, as the mineral spirit is highly flammable and can easily cause a fire hazard.
Step 4: Apply Primer
You can spray primer on it or paint it with a paintbrush. A primer is an undercoat that gives your paint a good finish by giving it something to grip. It also fills in gaps and smoothes out the paint job.
The primers are usually paint-specific. You’ll need an oil-based primer because we’re using oil-based paint. You should also read the manufacturer’s instructions on the drying time to know when to spray on the paint.
It usually dries in 2-3 hours, enough for spray painting. You could also wait about 24 hours for it to cure. For the best results, apply at least two coats of primer. Then, depending on the shape of the metal, you may need to use a brush in some areas.
Step 5: Spray on the Paint
The next step is to paint. When spray painting, there is a specific way to hold the can. Hold the can 10 inches away from the metal and spray. Also, when spraying, make short and light motions over the metal several times while rotating the object.
This way, it won’t become too thick in certain areas and start dripping. Allow 45 minutes to dry before applying another coat, and repeat for opacity. You can also use a brush to paint intricate areas the spray can’t reach.
Step 6: Apply a Sealant
People often overlook sealants, but they make a huge difference. A sealed metal paint job is more rust-resistant and will typically last longer than one under the same conditions. Do not use the sealant until 36-48 hours when the paint has thoroughly dried.
Frequently Asked Questions
What Happens if You Paint Too Soon After a Coat?
When you paint too soon after a coat, the color will be uneven at the end of the paint job. Some areas would have darker blotches. It also causes the paint to crack, peel, and eventually fall off because some areas will be thicker than others.
How Do I Get Rid of Rust?
To remove rust from metal, especially for small pieces, you can soak the rusty object in vinegar overnight and scrub it off with a scouring pad the next day. If the material is heavily rusted, sand it down to reduce the rust before soaking it in vinegar.
Is Painting Metal Easier than Painting Plastic?
Painting metal is more challenging than painting plastic. Besides, painting both metal and plastic involves different processes entirely. However, you must consider that it rusts for metal, and you’ll need to remove it and prevent it from occurring too soon. Doing this can add more steps to the process.
Painting metal is easy if there’s no rust on it. The processes involved in sanding rusted iron are also relatively straightforward to the point and even more so now for you, as explained above.
Ensure you take the necessary precautions before you paint for yourself and your environment. Now you can paint like a professional. Please leave your thoughts and questions in the section below.