How to Sand Plastic for Painting or Repair (220–800 Grit Guide)

Painting or repairing plastic surfaces can be tricky—paint often peels or scratches if the surface isn’t prepped properly. Sanding plastic creates a textured surface that allows paint, adhesives, or fillers to bond securely.

Why Sanding Plastic Matters

Most plastics have a slick, glossy finish that resists adhesion. Sanding removes this slick layer and provides grip for paint or repair materials. Without sanding, coatings may peel or flake within weeks.

Best Sandpaper Grits for Plastic

• 220 grit: Initial sanding to remove gloss and scratches.
• 400 grit: General surface prep before primer.
• 600 grit: Refining scratches for smoother finishes.
• 800 grit: Final sanding before paint or polishing.

Tools You’ll Need

• Wet/dry sandpaper sheets (220–800 grit).
• Sanding block or soft pad for even pressure.
• Spray bottle with water for wet sanding.
• Plastic primer and paint (if finishing).

Step-by-Step: Sanding Plastic

1. Clean the surface. Wash with mild soap and water to remove oils and dirt.
2. Scuff with 220 grit. Use 220 grit (100-pack) to remove gloss and create adhesion points.
3. Smooth with 400 grit. Switch to 400 grit (25-pack) for even prep before primer.
4. Refine with 600 grit. Use 600 grit (50-pack) wet to reduce visible scratches.
5. Finish with 800 grit. Wet sand with 800 grit (25-pack) for a smooth surface ready for paint.
6. Prime & paint. Apply a plastic adhesion primer before painting for maximum durability.

Special Cases

For flexible plastics (like bumpers), avoid sanding too aggressively—use lighter grits like 400–600. For rigid plastics, 220 grit is safe to start with. Always test in a small area first.

Pro Tips

• Wet sanding minimizes heat buildup and prevents melting.
• Sand in circular motions for even results.
• Always use a primer designed for plastics before painting.

Aftercare

• Allow primer and paint to cure fully before handling.
• Protect finished plastic with wax or sealant for durability.
• Avoid harsh cleaners that can strip coatings.

FAQs

• Can I paint plastic without sanding? No—paint won’t adhere well to slick plastic.
• Is dry sanding okay? Yes, but wet sanding reduces dust and prevents heat damage.
• Do I need to go all the way to 800 grit? For glossy finishes—yes. For matte paints, 400–600 grit may be enough.

Watch & Learn

Prep plastic surfaces right: Get 220–800 grit wet/dry sheets in 25, 50, and 100 pack options. Shop fine sandpaper.