Acrylic is a water-based paint that can stick to most paint. But, can you apply acrylic over enamel paint?
You can apply acrylic over water-based enamel. But, oil-based enamel paint will need to be lightly sanded and then primed with a latex primer before you can paint over it.
This is because the oil-based enamel forms a thick glossy film that prevents liquid from penetrating it. However, sanding and priming will cover (and remove) its glossy finish.
Acrylic paint doesn’t stick to enamel because most enamel paints are oil-based, and water-based paints don’t stick over them.
But, acrylic sticks to water-based enamel because they are compatible since they use the same solvent (water). To apply it, you must light sand and prime the finish first.
Sanding helps to remove the glossy layer of the finish, and the primer forms a textured finish that allows acrylic to stick over it.
Enamel paints are used for covering building exteriors and outdoor objects. They are formulated with additives such as paint pigments, UV resistance, and moisture resistance. All these additives prevent paints from sticking over it.
If you paint directly over it, the new coating will peel off within days. In addition, the presence of oils in the enamel will also discolor the acrylic finish.
How to Apply Acrylic Over Enamel Paint?
Painting acrylic over enamel isn’t hard, but the task can be time-consuming due to the level of surface prep required. Water-based enamel paint can be prepped in less than an hour, while the oil-based type takes a few hours.
Here are the tools you need:
- A Scrapper
- Rubbing Alcohol
- Chemical-Based Paint Stripper
- Synthetic Bristled Brush
- Fine-Grit Sandpaper
- Latex Primer
- Acrylic Paint
- An Oil-Based sealant (Optional)
1. Remove The Glossy Topcoat
You can skip this step if you are painting over water-based enamel.
Oil-based enamel, when dry, forms a thick layer that prevents liquid from penetrating. So, to paint over it, you must remove the glossy layer.
To do it:
- Scrape the Glossy Layer off – Use a metallic scraper to scrape as much paint as you can.
- Apply Rubbing Alcohol – Apply the rubbing alcohol to the glossy surface, leave it for 10-15 minutes, and scrape it again.
Rubbing alcohol contains isopropyl alcohol, and isopropyl alcohol is the active ingredient in the solvent that removes paints. However, use rubbing alcohol that contains more than 70% isopropyl alcohol. If the concentration is lower than 70%, rubbing alcohol won’t remove the glossy layer.
As an alternative, you can use chemical-based paint strippers. Chemical-based paint strippers are designed with chemicals such as methylene chloride, acetone, and turpentine. All of these compounds will remove the gloss on the oil-based enamel.
2. Sand Lightly
After removing the glossy layer, sand the enamel with fine-grit sandpaper. Sanding helps to smoothen the finish by removing imperfections and bumps. It also evens out the grain after removing the gloss.
You must only use ultra fine-grit sandpaper. Coarse or medium-grit sandpaper will remove the entire finish.
3. Apply Primer
You must apply two coats of latex or stain-blocking primer. The primer helps the paint to stick better and prevents the existing coat from bleeding through.
To apply primer, use a paintbrush. Wait until the first coat of primer dries before applying the next one.
4. Thin The Acrylic Paint
Since acrylic is too thick, you must thin it before applying it. To thin it, add water to it and stir the mixture until it has a consistent flow.
5. Apply The Acrylic Paint
You must apply two or three coats of acrylic paint over the enamel. To apply it, use a paintbrush or sprayer. Wait until one coat dries before applying the next. Acrylic paint dries within 2 hours.
6. Seal The Finish
Once the final coating dries, seal the finish with a sealant. The sealant will protect the finish from moisture, water, and other damage. You can use polyurethane or clear wax to seal it.
Mixing Acrylic Paint With Enamel
You shouldn’t mix acrylic paint with oil-based enamel paint. Both paints have different chemical formula and solvent that makes them incompatible.
If mixed, they will become unusable because the mixture will have a heavy paste-like appearance. If the mixture is used on a surface, it will remain sticky for days and won’t cure.
Since the oils in enamel paint will mix with water, the mixture wouldn’t have a clear solvent. So, it’s difficult for the solvent to evaporate from the coating.
However, you can mix acrylic with a water-based enamel. Both paints have the same solvent (water) and can be mixed. But, the finish may not come out nice because acrylic paints are more colorful and vibrant than enamel paints.
If you mix their water-based types, you will struggle to achieve a uniform color. So to be on the safer side, never mix them. Painting one over the other is a better option.
Acrylic Lacquer Over Enamel Paint
You shouldn’t put acrylic lacquer over enamel paint. That’s because acrylic lacquer contains turpentine (thinning agent) in its formula. Turpentine is known to remove enamel. So if you use acrylic lacquer over it, the thinning agent (turpentine) will lift the enamel paint underneath and ruin the finish.
Lacquers, by nature, aren’t designed to be used directly. They are usually sprayed, and since lacquer is too thick to be sprayed, you have to thin it first. Lacquer is thinned with turpentine or mineral spirits, both of these thinning agents will remove enamel paint.
However, you can apply acrylic lacquer over water-based enamel paint. Water-based enamel paints are thinned with water, so turpentine doesn’t affect it. But, the mixture will produce a color tint in the coating after a while, usually a yellowish tint.
Related Read: Can You Apply Enamel Over Latex Paint?
So, you can paint acrylic over enamel paint, but you need to prep the surface first. For water-based types, you need a light sanding. For oil-based enamel, you need to strip the gloss off the finish first.
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,