Crafting activities bring about a sense of achievement. It is also essential to preserve these precious pieces of art. Plastic crafts are in trend, but they tend to lose their color easily. So you might look for a permanent solution to preserve them.
Acrylic paints are not suitable for applying on plastic. But there is an easy way to make them long-lasting on your plastic crafts. That way is sealing the paint with an appropriate topcoat.
So, want to know how to seal acrylic paint on plastic? We cannot guarantee a permanent paint job, but we can surely guide you in making acrylic paint last longer on plastic. Let’s get crafty!
There are several ways you can seal plastic crafts. Acrylic paints are little particles of plastic suspended in a solvent. They are self-sealant, so there is hardly any need for another sealer. But you can go a few extra miles to protect the paint because plastic surfaces need extra protection.
Hence, we will discuss few methods that can make acrylic paint long-lasting on plastic.
1: Use Polycrylic for Crystal Clear Finishing of the Craft:
Polycrylic is a brand name of a water-based protective paint sealer. It is produced using polyacrylate along with polyurethane. The topcoat is available in high gloss, semi-gloss, matte, and ultra-flat sheens. It is suitable for indoor projects mainly.
# Spray on polycrylic:
The spray polycrylic finish is fast drying, crystal clear coat which does not yellow or darkens over time. It is less durable than polyurethane but clearer. The polycrylic spray formula lays evenly on the plastic surface. You can easily apply thin layers of the polycrylic finish and let it dry for 2 hours. Then apply 2 or 3 more coats to finish the project.
Using a roller or brush to apply the finish gives you more control over the application. The formula is the same as the spray finish.
2: You can Choose to Apply Polyurethane for Durability:
Polyurethane is more durable than polycrylic. But the water-based polyurethane gives a yellowish tone after drying. It can alter the color output you want from your craft. You can brush on the formula same as the polycrylic roll-on method.
Polycyclic and polyurethane are self-leveling and are appropriate for big projects like toy cars, figurines, outdoor furniture, flowerpots, and many more.
3: Acrylic Polymer Varnish for Outdoor Crafts and Furniture:
Acrylic polymer varnishes are available in matte, gloss, and satin. Satin is something between matt and gloss, so pick carefully. Here’s something to be noted;
Satin is the top choice of experienced crafters and DIYers. It seals acrylic paint and is made for that purpose. The acrylic polymer varnish is formulated with UV protection which protects the projects from discoloring.
Acrylic Polymer Varnish=>
4: Acrylic resin varnish is better for detailed crafts:
Acrylic resin varnish is very strong and durable. It is used in small projects requiring stiff and strong surface protection like costars, jewelry beads e.t.c. The finish is glossy and shiny that doesn’t become cloudy after a thick coat.
5: Use Mod Podge to seal acrylic paint:
Mod podge is a diluted permanent white glue with medium toughness, suitable as a top coat on acrylic paint. The glue also acts as a top coat on plastic crafts.
First, choose the type of finish you want for your project. It may be matte or glossy. Mod podge gloss luster will have a glossy finish. So it depends on the final look you desire, which type of glue you will use.
How to use Mod podge to seal acrylic paint on the plastic surface?
Here is a step-by-step application guide if you want to use Mod podge as a topcoat on your craft. Let’s check it out:
Step 1. Painting the plastic:
You have to apply more than one coating of paint to make it permanent. However, several thin coatings are better than one thick coat. So take your time to paint the project.
Put on the color with even strokes. The brush should be fine and has soft bristles, so the paint looks sleek. Now let the paint dry for the topcoat.
Step 2. Coating the plastic:
Choose a brush that you will not use for painting because it will become stiff if you use it for applying glue. So use a brush that is specified for glue application.
Don’t use a worn-out brush because it will apply glue unevenly. But when you apply the glue, the layer needs to be even. Patchy layers will dry with a texture that the craftsman did not intend. It is not self-leveling. So meticulously apply the sealing coat.
Take the glue with the brush and apply it to the painted surface. Be sure to check and confirm that the paint is dry. If the paint is still damp, the mod podge application will smear it, and your entire project will be ruined.
The coatings need to be light. Heavy coatings will not dry as fast. Therefore, two or more light coatings are better than one heavy coat.
Step 3. Drying:
It will take 15 to 20 minutes to dry the thin layer. When the coat is dry to the touch, add subsequent layers. For long-lasting results, add more than one coat.
Don’t hang up the project or use it until it’s been dry for 24 hours. For Hard Coat, we recommend letting it dry the project for 72 hours.
Because a hard coat is typically for furniture, you will have to wait for 72 hours before placing anything on the furniture. Mod podge is preferable to use with acrylic paints rather than latex paints, as it makes the latex paint formula bubble up.
Its coatings are good for toys, bottles, plastic furniture, and flower pots. Besides, it helps prevent scratches on the paint surface. Mod podge also protects the paint from chipping and darkening over time.
How to use primer for acrylic paint on plastic?
Preparation is the key. Peeling will occur if you don’t prepare the plastic surface properly. As a result, it will increase the adhesion of the paint on the plastic surface.
The preparation involves sanding, cleaning, and priming. This will help you create a lasting craft project.
What happens when if you skip preparation?
In case you skip preparation of the plastic surface, the paint does not adhere to the plastic. If you apply a primer before painting, it helps with the adhesion. Yet it is not enough because, after some time, the paint peels off.
The proper way of preparing the plastic surface for acrylic painting is by making the surface rough. However, most of the plastic surface you will work with will be smooth and deburred.
Paint or primer will not stick to this surface. Instead, you have to sand the surface with fine-grit 200 to 220 sandpaper, or you can also use Scotch Brite pads to make the outer layer grainy.
Then wipe the dust away from the surface with a clean cloth. The surface should not have any dust.
Finally, to clean off any leftover oil or dirt, use mineral spirit or isopropyl alcohol with a cotton pad.
Now it is time for the primer application. There is some research necessary before you apply a primer on plastic. It should be compatible with the type of material you are working on. Therefore read the labels and choose a primer that can stick to different types of plastic surfaces.
As you may know, primer formula should be specially formulated for plastic surfaces. This primer will establish a foundation that helps the paint stick.
Apply the spray primer evenly on the clean and dry plastic surface. You have to consistently hold the can at the same distance from the craft.
To avoid pooling in one spot, you have to keep moving it. The primer will conceal different colors of the plastic that will affect the tone of your acrylic paint.
It will create a blank canvas for the acrylic colors to pop. Let the primer dry completely, then apply paint.
Which types of finish are best to use for acrylic paint on plastic?
It depends on the project you are working on which type of finish you will use. Earlier, we saw different methods and different types of sealers for plastic; they have different outputs.
You can weigh the advantages and drawbacks of these sealants and decide. But our honest opinion is to seal the acrylic paint with an acrylic sealer. Acrylic finishes have more sheen options and are long-lasting.
Benefits of sealing acrylic paint:
The sealing coat provides protection to the paint. It protects from scratches, dirt build-up, and UV rays that darken the paint when the project is kept outside.
Also, handling causes friction to rub off paint from places where it is touched often. The topcoat also prevents paint smudge and peeling. It makes the finishing look glossy and bright. But you can adjust the final texture according to your wish. So seal your acrylic paint on plastic with an appropriate sealant.
Question: What is the best method to Keep Paint on Plastic Surfaces Permanently?
Answer: There is a saying that nothing lasts forever, but you can follow some procedures to make the paint last longer. The method is sanding, cleaning, painting, and, last but not least is sealing. Also, there is a golden rule of thin and multiple layers. Don’t do one or two thick layers.
Question: What Kind of Paint & Sealer to Use on Plastic Cups?
Answer: The best paint for plastic cups is acrylic paint because it is versatile. You can paint details with thick paint or airbrush whole cups with a thinner version of it.
A recent formula is specially formulated for plastic called “Paint for plastic,” which adheres to plastic easily. For sealers, you can use crystalac, which is FDA compliant in terms of food safety.
Question: What types of paint & Sealer to use on plastic craft projects & ornaments?
Answer: Because acrylic paint is bright and versatile, you can apply it to ornaments and plastic crafts. In addition, you can seal the acrylic paint with Acrylic polymer varnish or acrylic resin.
It is a great idea to upcycle old plastic so you can incorporate them into your crafts. The DIY projects help the environment by lessening plastic waste and making decorations for your home. It’s a win-win situation!
Don’t throw away plastic furniture and toys that lost their original color. Instead, repurpose them and seal them with a suitable sealer for acrylic paints on plastic which will last for years.
Hi, I am Rogers Weber, the man behind Solvesonic. I am a mechanical engineer. I use many kinds of tools almost every day at my workplace. I love to write about tools, painting, home improvement, and DIYs. I enjoy helping people to solve their problems through my website. => Follow me on Twitter