Painting plastic can sometimes result in peeling, flaking, bubbling, or chipping. So does spray paint stick to plastic and are there special techniques involved?
Most general-purpose spray paints stick to plastic. However, the surface usually needs to be sanded and primed before painting. Paints specifically designed to adhere to plastics are Krylon Fusion All-In-One (formerly Krylon Fusion for Plastic), Valspar Plastic Spray Paint, and Rust-Oleum Specialty Paint For Plastic Spray.
In this article, I’ll show you:
- How to select the right spray paint
- How to prepare plastic for spray painting
- Step-by-step guide to spray-painting plastic
- Additional tips and three alternative paint options
What Type of Paint Sticks to Plastic?
There are many types of plastic, from PVC to PET, and most plastics consist of petroleum or natural-gas-based products. Plastics are popular because they are easy to clean and make effective liquid containers.
Plastics are liquid-resistant, and most plastics repel regular water- and oil-based paints. For a longer-lasting finish, you should use specific paints and primers for plastics.
You can try to spray a plastic surface with a regular can of spray paint, but you will find that it cracks or peels off the surface as soon as it dries. A regular can of spray paint will stick better if the plastic is rubbed with sandpaper.
Is it Better to Sand Plastic Before Spray Painting?
As with any painting, start with preparing a clean and residue-free surface. Chemicals on the surface of the plastic resist any paint, even plastic-specific paints. Sanding the plastic creates more surface area and gives the paint something to cling to.
A rougher surface is better for paint adhesion, though you do not want to use sandpaper that will leave visible scratch marks. For the best results, use 220-grit wet and dry sandpaper.
After sanding, you can also wipe the plastic down with a damp clean cloth to help remove any oils and dust that were clinging to the plastic. This is a suitable time to apply painter tape to mask off any areas that you want paint-free.
Do You Need a Plastic Primer to Spray Paint Plastic?
Some plastic primers will cling to bare plastic, but you will find that that adhesion is still better if you sand it first. Spray plastic primers can come in all-in-one options, with the primer and paint in a single spray can. You may need to apply more than one coat of primer before using your paint.
When spraying on the primer, hold the can at least twelve inches away from the surface; this helps to prevent dense patches and drips. The further away you hold the nozzle, the thinner the coat, but this will also waste more paint into the air.
Once you commit to spraying, try to keep the nozzle the same distance from the surface as you move around to spray the rest of the plastic. Try to keep your movements consistent and at the same rate of movement. Wait until the surface is dry before laying another coat of primer or paint.
How to Spray Paint Plastic
Some plastic surfaces are harder to paint, such as laminated surfaces, vinyl fabrics, and plastic vanities. These plastics may need more aggressive preparation by using coarser sandpaper and stronger primers.
The following process should work well for all plastics, including – furniture, toys, containers, trash cans, flowerpots, and decorations.
- Protection sheet, old newspaper
- 200- to 300-grit sandpaper
- Isopropyl alcohol
- Plain liquid soap
- Painter’s tape
- Krylon Fusion All-In-One spray paint (formerly Krylon Fusion for Plastic)
- Plastic primer
- Protect – Set up your paint area; you need somewhere clean to rest the plastic object while it is drying. If it is a plastic fixture in your home, lay down protective sheeting on the floor or old newspaper beneath and around it.
- Sand – Use 200- to 300-grit sandpaper to rough up the parts of the plastic that will receive paint. Wet and dry sandpaper will help you to not gouge out the plastic.
- Clean – Use isopropyl alcohol, then mild soapy water, to remove leftover chemicals and dust. Dry the surface off.
- Mask – Mask-off any anything that you do not want to paint on, with painter’s tape.
- Primer – For quick projects, you may not care about this stage. But if you want your model figurine to look good, it is worth using a plastic-specific primer.
- Spray – Keep the spray nozzle at a fixed distance and move consistently across the plastic. Avoid over-spraying, as this will drown the surface and lead to drips. As a quicker option, you can try an all-in-one primer and paint spray.
- Dry – Most sprays are touch-dry in under 30 minutes but check with the instructions on the can. Once it dries, you can add another thin coat if you think it needs it. Wait a full day for the paint to harden before using it.
Tips for Spray Painting Plastic
Before using a spray, be it primer or paint, shake the can well before use. Spray cans combine a thinner, the paint, and the propellant. These chemicals will separate in the spray can over time, and the paint will fall, congeal, and cling to the metal base.
Inside the can, there are two small marbles to help you mix the thinner back into the paint by shaking it. Swirling the can around will help to scrape the paint away from the base and give you a more consistent color during spraying.
Have mineral spirit on hand to clean off misses and drips. Wear gloves because the paint will hit your finger as it leaves the nozzle, and you may need to adjust your plastic object as you go.
You should do your spraying outside and wear a mask while doing so. You do not want to be breathing in any paint -goggles are also a good idea.
For small objects, you will want to raise them off the protective sheeting with scrap wood. This will prevent your object from sticking to the sheet or newspaper.
Alternative Paints for Plastic
Paint for plastic ranges from cheap to expensive. There is little point in using the best paint on twenty-year-old plastic garden furniture. But you may want a special-application paint for the benefit of grip or appearance.
Here are a few specialist suggestions for spraying plastic:
Age-Effect Spray Paint
This spray paint is suitable for most materials, including plastics, vinyl, and fiberglass. The weathered-steel effect can add charm to a company sign or disguise furniture to make it look like metal.
Rubber Coating Spray Paint
Plastics do not weather well, and this paint protects from acids, moisture, heat, and vibrations. The rubber coating is also ideal where you want a non-slip plastic, such as the handles of garden tools.
Vinyl Spray Paint
Vinyl and other plastic fabrics need paint that is more flexible and elastic than what typical plastic sprays can offer. This enamel vinyl paint is suitable for luggage, car seats, floor mats and will not rub off, crack, or split.