Spray paint cracks, wrinkles or bubbles can keep your project from looking perfect. The good news is that imperfections in paint finishes are preventable. And, if they do happen, you can take steps to remove them.
What Causes Spray Paint Cracks?
Spray paint cracks can occur if a coat of spray paint is applied too thickly. When a coat of spray paint is too thick, the outer layer can dry while the paint underneath it remains wet. As the paint below slowly dries, cracks can occur on the surface. That’s why it’s smart to apply multiple, thin coats of spray paint rather than a single heavy coat.
Spray paint cracks can also occur if you’re working in extreme temperatures. If it’s too hot, humid or cold, spray paint can dry too quickly or too slowly and result in cracks.
If it’s hot outside, the paint’s top layer can dry too quickly, trapping wet paint beneath it. This can lead to cracks. Cracks can also develop in the paint if the surface of the object you’re painting is too warm.
Additionally, humidity can result in longer dry times, which means you’ll also need to wait longer between coats of spray paint.
Spray paint also takes longer to dry and cure when applied in cold weather. This can also lead to spray paint cracking.
Depending on the appearance, paint cracks may also be referred to as crazing, alligatoring or mud cracking.
These issues typically can be avoided if you apply spray paint at the appropriate thickness and within the recommended temperature and humidity levels. For instance, spray paint often delivers best results when applied between 50 and 90 degrees Fahrenheit and when the humidity is below 65 percent. Check your product’s label for specific recommendations before beginning your spray paint project.
What Causes Spray Paint Wrinkles?
Spray paint wrinkles make paint look raised or crackled. They can occur if you apply a coat of spray paint over a previous coat that has not appropriately dried. Improper drying generally happens if you apply the spray paint too heavily, if you apply the second coat too soon after the first coat, or if you’re painting when it’s too cold, too hot or too humid.
You can generally avoid spray paint wrinkles by applying thin, even coats of spray paint in the weather conditions stated on the can, and by following the recommended timeframes for drying and recoating.
What Causes Spray Paint Bubbles?
Spray paint bubbles are tiny pockets of trapped air. When they break, they can leave small, round depressions in the paint.
If you plan to use a gloss or semi-gloss spray paint on a porous surface, applying a coat of paint primer first can help prevent spray paint bubbles. Also, be sure to follow the directions on the can, which include ideal temperature conditions and dry and recoat times.
How Do You Prevent Spray Paint Imperfections?
Before you apply spray paint, ensure that the object is free of dirt or waxy buildup. An all-purpose cleaner and degreaser can help remove dirt and stuck-on substances and help the paint adhere. After the surface is clean and dry, you can start painting.
Always follow the directions on your spray paint can, which typically include recommended dry times, recoat times and ideal temperature ranges for painting. Painting when it’s too cold, too hot or too humid can affect the drying process and could make the second coat of paint susceptible to blemishes.
It’s also important to avoid painting in direct sunlight because imperfections can result if the surface of your object is too warm.
Most spray paint contains solvents. It's important to apply paint in thin coats so that the solvents can escape. Applying oil-based spray paint too thickly can trap solvents and result in wrinkles or cracks.
How Do You Remove Spray Paint Cracks, Wrinkles or Bubbles?
If you notice cracks, wrinkles or bubbles in your spray painted surface, don’t panic. You can still achieve a smooth surface by following a couple of key steps.
First, be sure to let the paint dry for at least 24 hours. This allows time for solvents trapped under the imperfections to evaporate.
After the paint is dry, use sandpaper to rub the imperfections out. Choose sandpaper with a grit rating of at least 220 for smaller blemishes, and 180 or less for deeper ones. Once you’ve sanded off the imperfections, wipe off the sanding dust.
Sanding can expose undried solvents, which are not always visible. That’s why it’s a good idea to wait another 24 hours, allowing them to fully evaporate. After 24 hours, you can complete your project with a new, thin coat of spray paint. Be sure to follow the recoating instructions on the can’s label for best results.
Luckily, you can usually prevent spray paint from cracking, wrinkling or bubbling, and if it does happen, you can correct it. Achieving a smooth surface without paint cracks or wrinkles will make it look great and help the paint job last longer.