It is not at all easy to paint on plastic. Unlike wood, this material is not porous and, consequently, the paint does not adhere; however, with proper preparation, you can succeed in your intent. But remember that depending on the type of product you are using and the kind of plastic you want to color, the paint layer may eventually chip, especially after heavy or frequent use.
Steps
Part 1 of 3: Prepare the Surface
Step 1. Choose the object you want to paint
With the right preparation, you can color anything, such as furniture, figurines, containers and knick-knacks.
Not all plastics are suitable for this project; among these, consider laminate floors, shower and tub stalls, or kitchen countertops.
Step 2. Clean the item with warm water and a mild dish detergent
By doing this, you eliminate all traces of dirt and minimize the work you will have to do later. Use a soft cloth or sponge to wash smooth surfaces and instead an abrasive pad for rougher ones (such as outdoor furniture); when finished, rinse the object and pat it dry.
Step 3. Lightly sand the surface with 220 or 300 grit sandpaper
Apply gentle pressure and make circular motions to avoid scratches, then wipe the object with a dust-catching cloth.
Sanding is an important step because smooth surfaces become a little more grainy, allowing the paint to adhere better
Step 4. Clean the surface again using denatured alcohol
This is essential for removing any oily residue that could interfere with the application of the paint; if you ignore this step, there is a greater chance that the color will splinter later.
Handle plastic with great care; hold the object by the edges or wear disposable gloves.
Step 5. Protect any parts you don't want to color with masking tape
You should do this even if you plan to use a brush instead of spray paint, because this way you get sharp, well-defined lines between the colored area and the original.
Step 6. Apply a coat of primer
You should choose a product that adheres well to the plastic to even out the surface and provide the color with a layer to bond with. Spray products are the easiest to use, but those that apply with a brush are also fine.
- Wait for the adhesive to dry completely before moving on to the next steps.
- If you have decided on a spray primer, remember to protect your work table and proceed in a well-ventilated area.
Part 2 of 3: Painting the Surface
Step 1. Prepare the work area
Choose a room with good lighting. Cover the table with newspaper or a cheap plastic tablecloth. If you have decided to use spray paint, you should proceed in an environment with good ventilation or, better yet, outdoors.
If there are areas of the object that you do not want to paint, protect them with masking tape
Step 2. Choose a paint for plastic
That spray is perfect for that material, but you can decide to use acrylic, enamel, or modeling. You'll get even better results if you make sure the product is formulated to adhere to plastic; read the label looking for words like "for all surfaces" or "for plastic".
Step 3. Prepare the color if necessary
Some products are ready to use as they are, while others need a little preparation. Before you get to work, read the label on the can or tin to see if there are any specific instructions.
- Shake the can for a few minutes; this way, you prepare the spray paint by mixing it for a smoother application.
- Dilute the acrylic product with water until a creamy consistency is obtained; with this foresight you will encounter fewer difficulties while working and minimize the visibility of the brush strokes.
- Some enamel or modeling paints need to be diluted, typically with a specific solvent that you can find on the same shelves along with those colors.
Step 4. Apply a light, even coat of paint
Don't worry if it's not perfectly covering at first, then you'll spread other layers; this step is very important, regardless of whether you are using the spray can or the brush.
- Hold the spray nozzle 30-45cm from the surface and move the can from side to side steadily.
- Apply acrylic paints with brushes with taklon, kanekalon, or sable bristles.
- For nail polish or modeling products you should use stiff bristle brushes that are on sale on the same shelves as these colors.
Step 5. Smear other layers of color
Let each coat dry before applying the next; alternate the direction in which you apply each layer: if you made horizontal movements for the first, use vertical ones for the second, and so on. The number of coats depends on your personal preferences and the type of coverage you want to get; usually, only 2 or 3 are spread out.
Drying times vary according to the type of paint; in most cases 15-20 minutes is enough, while for the final layer you should wait 24 hours.
Step 6. Wait for the color to dry completely after applying the last coat
At this point, the project is finished and you can use the object. If you'd like to add details or a protective finish layer, read the next section of the article.
If you have applied masking tape to protect some areas, remove it at this time; peel it off carefully so as not to accidentally chip the color
Part 3 of 3: Finishing Touches and Sealing the Surface
Step 1. Fill in any nicks or colorless areas by applying the paint with the brush
Inspect your artwork carefully; if you notice spots where there is no paint, touch them up with another color and a fine brush. If you have previously used spray paint, you should use an acrylic product of the same shade for this.
Step 2. Add some details, stencils or any other decoration you like
This step is entirely optional, but it can customize or embellish the object, especially if it is a figurine or an ornament. Here are some ideas to get you started:
- Lay down some stencils and apply the paint by spray or with a foam brush;
- Use a sharp brush to paint spiral decorations or designs;
- Add highlights with lighter shades of color and shade other areas with darker shades.
Step 3. Apply a thin coat of polyurethane sealant to make the color more resistant
You can use a spray or brush product, but know that the former guarantees a smoother and more homogeneous finish. Apply a single light coat and wait for it to dry for at least half an hour; if necessary, spread other layers 3 minutes apart.
- Choose a sealant with the finish of your choice: matte, satin or glossy.
- Remember that several light layers are always better than just one very thick one; if you apply too much sealant, the surface will become sticky.
Step 4. Wait for the paint and sealant to dry completely
Just because something feels dry to the touch doesn't necessarily mean it is completely dry; read the instructions on the product packaging to know the drying and curing times.
Several enamel paints need to rest for several days; meanwhile, they may be sticky and prone to nicks or other damage
Advice
- If you only need to paint a part of the plastic object, avoid the sanding step, otherwise the difference in surface texture becomes evident.
- If you are only painting a few details on a plastic surface, such as flowers, choose the paint effect that matches the rest of the material: matte or glossy.
- Some types of paints are more resistant than others; for best results, look for products specific to plastics.
- If you are coloring several sides of an object, such as a box, work on one face at a time.
- If the spray paint drips or drips, you are applying too thick a coat; pull the nozzle away from the surface and spray with a steady waving motion.
Warnings
- Always work in a well-ventilated room to avoid inhaling toxic vapors from paint, sealant, or mineral spirits.
- The paint of the objects you use constantly scratches over time.
- Some types of plastics do not absorb color, no matter how carefully you prepare them; in these cases, there is very little you can do.
