Painting On Metal: A Step-By-Step Guide For Beginners

Michael Daly
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Painting On Metal Requires A Squeaky Clean Surface

Squeaky clean is the most essential and basic requirement for painting on metals.

The surface of the item you want to paint on must be completely free from grease, oil, and dust. Any contaminants will ruin your painting job.

To remove oil and grease, use paint thinner to wipe the item clean. You can also use denatured alcohol or acetone.

Nowadays, you can also find cleaning products specifically developed for metal surfaces. These products are specially designed to remove completely any trace of grease, oil, or dirt, and organize the surface in the way that makes painting an easy job.

But What About Rust Build Up?

This is one of the first questions that you will surely ask yourself. So, the answer to this is, yes, it does cause rust. But not equal to the rust that you get when you leave wet storage in a brand new toolbox, or if you leave lawn equipment lying around in the rain.

Tools that have oiled finishes, if not used, will corrode faster. If it is an item you use a lot, however, it will still corrode. But without proper use, it won’t build up in any extraordinary amount.

Unlike oil, polyurethane finish will not stick around once you use it. Once you start using it, the finish bonds to the metal and keeps out the water and air. This way, you get a protective barrier that will not let corrosion take a foothold.

It is a known fact that older paints will settle and lose their protective barrier with time. This is what causes premature rusting. Paints that have a modern formula with the plasticizer to keep the finish on the metal, however, do not lose their protective barrier.

That means you can leave the equipment out in the rain and not worry about the rust.

The Rust-Oleum is extremely versatile. This is one of the ways it makes it easy for you to finish your project. You can cover almost anything including wood, metal, porcelain, and masonry.

Preparation is the most important part of painting and anyone who says different is a dirty liar!

Think of any job you have been part of when you weren’t prepared for it: it makes you feel uncomfortable, unsure, untogether and generally stressed. Not the best way to work most of the time. And painting is no exception.

There’s no point having all the right tools for the job, having bought the right paint and having the right surface to paint on if you haven’t planned your work!

By planning your work, it will take you less time and require less effort to get the result you want.

So, to help you prepare a project properly, here’s a list of the 10 stages which I always follow when preparing to paint. There are also some helpful tips at the end for when you’re doing the actual painting.

Check the area.

Before you even touch a brush to the wall, take a look at where you will be painting.

Are the electrics and wires you need to get behind covered so there is no danger of damage? Are any existing fixtures and fittings covered to prevent overspray? Are there any areas on the floor you need to protect?

When Painting On Metal, You Must Have Ample Tooth

When painting metal, the final look depends in large part on the basecoat you use and the number of layers you apply. For example, you have to take account of the basecoat’s adhesion capabilities and the basecoat’s not sticking to the metal. You also have to take care of the surface texture and uniformity of paint.

Make sure that the basecoat has good adhesion into the metal; it is able to withstand the paint load without flaking or peeling.

It’s not a good idea to use oil-based paint in this case, because it’s more likely to absorb into the layer than a water-based paint. Also, the fact which you are painting metal will get you a lot of heat, so be sure to check the paint’s temperature resistance.

While you need to make sure that the paint can withstand heat, you also need to make sure the paint is suitable for your surface. Different surfaces require different kinds of paint.

For example, you need to prepare the metal surface before applying the paint, sanding and buffing the metal to make it have a smoother surface to which the paint will stick better.

The choice of the paint depends on the use of the finished item.

Making Your Surface Ready For Prime Time

Painting on metal calls for a different approach than painting on wood or walls.

The surface has a lot of moister in it, so you have to make sure to do the prep work for it.

The first thing you need to do is get a paint scraper and allow the surface to warm up on a nice sunny day.

Use the scraper to scrape away any rust or grime from the surface. This will work best if you scrape in the direction that the metal would have contracted from the heat.

Once you’re done, hose down the surface with a strong stream of water and let it set. Eventually, you should be left with clean, bare metal.

Next, you’ll want to sand down the surface using an aggripper. You should sand the surface with an aim of a fine grit all over. Wipe away any dust and dirt with a cloth.

Go over your surface with a fine sand and steel wool.

You may want to sand just before painting the metal to prevent the metal moister from pitting the paint. If you are going to paint your metal right away, give the surface time after securing the rust proof primer.

Optional Step: Gesso On Top Of Self-Etching Primer

Gesso is a white paint designed for use on a variety of surfaces. Typically used to create a textured surface on which an artist can later paint, it also makes a good last-minute primer for metal artwork.

If properly applied to your metal surface, it will provide a smoother base for your paint than a regular primer will. It's a bit more work than your average primer, but is worth the extra elbow grease if you're going for a finished look.

The formula for regular gesso is: one part water to one part gesso. This means one cup of water should be mixed with one cup of gesso until smooth.

The gesso can be applied with a brush or roller cover. Once the surface is completely covered, let it dry for at least 48 hours before using your metal as a canvas.

If your gesso shows signs of cracking, you can fix it by lightly sanding over the areas that show signs of damage. Once sanded, apply another coat of gesso and let it dry as per usual.

Should You Use Oil Or Acrylic On Metal?

There are three basic prep steps that apply to any type of exterior painting preparation and requires you to clean, scrape, and sand your painting surfaces often.

Step 1: Making sure you have a clean surface to start with is simple and requires only two basic tools. First, a garden hose with a nozzle attached and if the surface you can’t reach with a garden hose, a stiff-bristled brush.

Step 2: After cleaning your surface with a hose, apply an abrasive material like steel wool to areas that have rust or paint that needs to be stripped off. A medium to light steel-wool grade is recommended.

Step 3: The final prep step depends on the type of paint you want to use to paint your surface. For oil and acrylic paints, you should sand the surface using a sanding block. Simply change out the sandpaper on the sanding block as it becomes caked with paint.

Chemical-treated surfaces require a slightly different preparation. For treated steel, pickled surfaces give the best adhesion for exterior paints like solvent and water-borne paints.

The pickling process is essentially 5 percent muriatic acid and 95 percent water. Simply spray the surface down and allow it to set for 5 minutes.

Don’t Use Your Typical Varnish When Painting On Metal

Painting on metal isn’t as complicated as you might think. However, you want to make sure you get the job done right the first time! After all, the painted finish is very hard to fix once it’s on the wall!

The hardest part of deciding how to paint on metal is choosing the right paint. This is because you need a paint that is specifically designed to adhere to metal surfaces.

If you are painting a corrugated metal surface, use a primer designed to stick to corrugated surfaces. These products are specifically designed to fill in the gaps and holes in this type of surface.

All-purpose paints are not effective on a corrugated surface because they do not fill in the gap and holes as well as these specialty products.

If you are painting on a smooth surface, you will need to prime the surface before you begin painting.

Primers are just as important as paints and will give you a better paint-over in the long term. They serve as a protective coat so that the metal doesn’t react with the paint and discolor it. The top coat will then bond to this primer to ensure the paint does not chip or peel off.

Final Thoughts For Painting On Metal

One of the really neat things about DIY projects and crafting is that they are fun to do with absolutely no expectations. You don’t know how the project will turn out, but that is the fun of it!

If you are still looking for other metal crafts to try, you could try any of these:

  • Metal Mood Rings
  • Metal Page Markers
  • Metal Tray or Frame
  • Metal Phones Cases
  • Metal Book Ends
  • Metal Bird Bath

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{1}. Clean the surface. You need to start with a clean metal surface in order to make the job easier. Use a degreaser to clean the surface thoroughly before applying the paint.
{2}. Apply the undercoating. After removing all gunk and dirt, it’s time to apply a primer. Undercoating is an essential protective coating for the metal. It provides a base for the paint and protects the metal from rust.

You can apply undercoat by pouring it over the area and using a paint roller brush or by simply brushing it on. Don’t forget to wear a protective mask and gloves while painting.

You can also sand the surface of the metal before applying the undercoat. But make sure you have cleaned the surface thoroughly that no other dirt remains. The metal painting experts recommend applying the undercoat first and then sanding it. You should wipe the surface clean once sanding is completed.

Apply a couple of coats of primer. You need to apply the primer in different layers for a smooth finish. Apply the primer and let it dry for 6 to 8 hours. Clean the surface and then apply another coat of primer once the first coat has dried.

The primer slows the penetration of paint and reduces the chance of measuring spills.