Enamel is a durable paint that has a glossy finish when dry. In addition, the paint has impressive adhesion qualities. So, does enamel paint need a primer?
Enamel paint doesn’t need a primer for clean, even, and dry surfaces. However, if the surface is wet, has imperfections, or is uneven, you must apply a basecoat first.
The primer will fill holes, cover imperfections, and produce a smooth and even layer for the paint to stick to. For these reasons, applying one is recommended.
Can You Paint Enamel Without Primer?
You can apply enamel paint without a primer because the paint has impressive adhesive qualities and will stick to almost every surface. But, a basecoat will produce a smooth and textured layer that the paint can stick to.
Enamel has a thick flow that offers protection and a colorful finish to surfaces. When dry, it forms a glossy finish that repels moisture. So, for smooth and clean surfaces, a basecoat isn’t needed.
However, if the surface has imperfections, you must apply primer or basecoat first. The basecoat will fill the holes a surface has, cover imperfections, and help the paint stick better.
Also, if the surface is wet or has moisture, you must apply a stain-blocking primer to prevent water (or moisture) from bleeding through. If you don’t, the paint won’t dry or stick to a wet surface.
You must also apply a basecoat for non-porous surfaces such as plastic. Non-porous surfaces don’t have fibers (or pores), so the paint can’t penetrate them and stick. So, you must apply a base coat to the plastic and then apply the paint. Primers are formulated with extra binders (or additives) that help them stick to non-porous surfaces.
Also, if the surface is sealed, you must apply a primer first. A sealed surface won’t allow any liquid to penetrate, including paint. So, you must apply a basecoat over the sealed finish, and then paint over it.
Primer Types To Use:
The recommended primers to use for enamel paint are alkyd, acrylic, and shellac primers. Depending on the surface you are painting, you can choose one or the other.
Alkyd primer is a stain, moisture, and UV-resistant basecoat. It is oil-based and prevents wet surfaces from affecting the paint adhesion. You must apply this primer if you are painting over non-porous surfaces, such as plastic.
You can use acrylic (or latex) primers because they dry fast and adhere well. But, a water-based basecoat shouldn’t be your first choice for oil-based enamel, there are better options. However, for water-based enamel, this is the best choice.
This basecoat is good for drywall, plaster, and wood. However, it isn’t moisture-resistant, so don’t apply it over wet surfaces.
Shellac primers dry fast, have good coverage, and provide a smooth base for paints to stick to. They are stain-blocking and will prevent water or moisture from bleeding through. You can use them to cover water and smoke damage over walls.
Applying a basecoat before applying enamel paint to metal isn’t necessary. But, it will help the paint to stick better.
However, you must use a basecoat if the metal surface is rusted, wet, or damaged. If you don’t, the rust and moisture will bleed through the paint and change the color shade of the finish. Also, the dry time of the paint will increase, and the finish will turn tacky.
A stain-blocking primer will prevent moisture and rust from bleeding through the paint. It will also fill the holes in the metal surface and create an even base coat for the paint to stick to. However, if the metal surface is severely damaged, you must repair it first.
For metal surfaces, apply a shellac or oil-based primer. Avoid using water-based primers as they use water as their solvent, and if the metal has moisture, the base coat will get thinned (diluted). It also won’t stop moisture from bleeding through.
Rust in metal surfaces is created by a combination of moisture and air, which causes oxidation. The oxidation forms rust and peels off the finish from the surface. So, to avoid this, apply a moisture-blocking primer.
Related Read: How To Apply Enamel Over Latex Paint?
You must apply primer on plastic before applying enamel paint because plastic surfaces are non-porous and slick, so the paint won’t stick without a basecoat.
Plastic is a non-porous surface, and as such, no paint will stick to it. Since plastic doesn’t have fibers, paint can’t penetrate the surface and will slide off. However, primer is formulated with extra additives to allow it to stick to a plastic surface.
To apply enamel paint on plastic, sand the surface, apply one coat of primer, and then apply it. Sanding will produce a ridged layer over the surface to help the basecoat stick better. If you apply it without a primer, the paint will chip and slide off the surface.
You can apply enamel paint on wood without primer, but the wood must be clean, dry, and smooth. There are also types of enamel paint that come with primer in their formula, so you don’t have to apply it.
However, the paint won’t stick well if the wooden surface isn’t clean, dry, or smooth. That’s because the dirt and filth will prevent proper adhesion.
The wooden surface must be dry for the paint to stick. If the wooden surface is wet, it means the wood fibers are already filled with water, so paint can’t penetrate the surface. You must either remove the water from wood fibers or apply a coat of stain-blocking primer to allow enamel paint to stick.
If you don’t want to use a basecoat, you can just sand the wooden surface before painting it. Sanding will remove the imperfections and bumps from the surface.
Using a primer for enamel paint isn’t required, but it’s recommended.It will help it stick better and provide a smoother finish. However, applying a basecoat is only required if the surface is dirty, uneven, or wet.
Tony is a professional painter and an author of DIY Geeks. Tony has completed over 1,000 painting projects for his clients. It's safe to say he knows what he Is talking about,