Gloss paint is oil-based, and because of its high gloss, it is hard to apply. So, while applying gloss paint, you will run into different problems. Why do these problems happen, and how to fix them?
1. Gloss Paint Turning Yellow
Gloss paint is oil-based, meaning the paint particles are dissolved in oil. So, when the paint dries, the oily deposits left on the surface will start to bind and form yellow spots on the surface. After a few days, the gloss paint coating will have an amber-like appearance.
Unfortunately, you can’t fix the yellowish tint on the gloss paint. But, you can reduce the yellow spots by:
- Applying thin coats. This reduces the level of oils in paint.
- Sanding the paint with fine-grit sandpaper to reduce yellow spots.
- Leave enough time between coats so the oils can fully evaporate from the coating.
2. Bubbles in The Finish
Bubbles can appear in gloss paint during and after applying the paint. This is when air bubbles start to form on the paint layer. These air bubbles can also pop and cause tiny holes in the finish.
Air bubbles appear on gloss paint because of the following:
- Improper mixing – Before applying paint, you must mix it. If you stir the paint aggressively or too fast, air pockets will trap in the paint, and once you apply it, the air pockets will form bubbles in the coating.
- Using Rollers – Foam rollers are made from absorbent materials that soak up the gloss paint, leading to thick coats that can develop bubbles.
- Porous Surface – Porous surfaces, such as fresh wood, have pores on the surface that are filled with air pockets. So, if you apply gloss paint over a porous surface, the air inside the pores will form bubbles in the finish. To avoid this, apply a stain-blocking primer before applying paint.
To fix bubbles in gloss paint, pop the bubbles, sand the surface, apply a sealer coating, and re-apply the paint. Here is a guide on how to do this:
- Pop the bubbles on the paint coating.
- Leave the paint to dry for 20 minutes.
- Sand the gloss paint with fine-grit sandpaper.
- Apply 1 coat of sanding sealer over the surface and leave to dry.
- Re-apply the gloss paint.
3. Gloss Paint Is Peeling Off
The gloss paint will peel off if there’s poor adhesion between the paint and the surface. This happens a few days or weeks after applying the paint.
Here are other reasons why this happens:
- Filthy Surface – If the surface is dusty or filthy before applying the paint, the finish will peel off. That’s because the filth or dirt will prevent the gloss paint from sticking to the surface properly, leading to peeling paint. So, you must clean the surface before applying paint.
- Sanding Between Coats – When dry, gloss paint forms a thick glossy layer that prevents liquid from penetrating its surface, including paint. You must sand off the glossy layer to allow the new coat to stick. If you don’t sand the glossy layer and paint directly over it, the gloss paint will peel off because it can’t penetrate the coating or stick.
- Wet Surface – The surface must be dry before you apply paint. If the surface is wet (or affected by moisture), gloss paint won’t stick over it. Because of poor adhesion and the wet surface, the paint will peel off.
To fix peeling gloss paint, remove the coating and re-apply it.
Here’s a guide for this:
- Scrape the peeling paint with a paint scraper. You can use mineral spirits to soften the paint before scraping.
- Find the cause of peeling paint. If the surface is wet, dry it before painting. Or, if the surface is filthy, clean it and re-apply the paint.
- Sand the surface using fine-grit sandpaper.
- Apply stain-blocking primer.
- Re-apply the gloss paint.
You shouldn’t paint over peeling paint with another coat because the new coat will start to peel off too.
4. Tacky or Sticky Finish
It takes gloss paint 2 hours to dry. But, if the paint takes longer to dry, the finish will turn sticky or tacky. Gloss paint turns tacky if the paint takes longer to dry than usual.
Here are common reasons for this:
- Wet surface – If you apply paint over a wet surface, it won’t dry or stick. That’s because moisture (or water) in the surface will prevent paint from drying. This leads to a sticky finish.
- Cold Temperature – Paint takes two times longer to dry during moist or cold temperatures. That’s because the humidity levels will be high, and this causes the finish to remain wet for hours and turn sticky. To avoid this, paint when the temperature is above 50 degrees (F).
- Re-coating Too Soon – If you re-coat gloss paint too soon (before the coating dries), the finish will turn sticky. That’s because if the paint is still wet and you apply a coat over it, the solvent will be trapped between coats, causing the coating to remain wet and sticky.
To fix sticky gloss paint, increase the evaporation rate by exposing the coating to increased heat and airflow. The increased heat will increase the evaporation rate, which speeds up the drying time of gloss paint. Once the paint dries, the paint won’t be sticky anymore.
Here is a guide to do this:
- Turn on the hairdryer.
- Move the hairdryer around the paint coating.
- Turn on the fans in the room.
- Open all doors and windows.
- If possible, carry the painted item outside where it will be exposed to proper airflow.
If this doesn’t work, you must remove the paint, fix the issue that is causing the paint not to dry, and re-apply it.
5. Lumpy Gloss Paint
If you open the paint and see solid particles inside it, it means that the paint has gone lumpy. The solid particles are paint particles that have become clogged or packed together. The paint gets lumpy if air gets into the paint containers and clogs the paint up.
To fix lumpy gloss paint, add a thinning compound to the paint to dissolve the lumps. After, stir the paint to achieve a consistent flow. For gloss paint, the thinning compound is mineral spirits.
Here is a guide to do this:
- Pour the lumpy paint into a clean paint bucket.
- Add mineral spirits to the paint. Don’t use too much mineral spirits as you can over-thin the paint.
- Stir the paint using a paint mixer or turning stick.
- Test the paint.
6. Cracking Finish
Gloss paint coating will start to crack (or split) if the paint dries too fast. If you expose the paint to heat for too long, the solvent will evaporate too fast, and the paint particles won’t have enough time to harden or compact naturally. Since the paint particles aren’t hard or compact enough, the paint will start to crack.
Gloss paint will also crack if you over-thin it before applying. Since the paint is too thin, it won’t properly cover the surface, and the paint will crack.
To fix a cracking gloss paint finish, sand the surface with fine-grit sandpaper, apply a primer coating, and add two more coats of paint. If the paint continues to crack, remove the entire finish, apply stain-blocking primer, and re-apply the paint.
Since gloss paint has a thick flow, it’s hard not to run into problems while applying it. So, we have listed the 6 most common mistakes for gloss paint, why they happen, and how to fix them.
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,