Essential Grits for Polishing Epoxy Resin Projects (400, 800, 1500, 3000 Guide)

Epoxy resin creates stunning glossy surfaces for tables, countertops, jewelry, and art, but achieving that crystal-clear shine requires careful sanding. If you stop too early or skip grits, the surface can look cloudy or scratched. With the right sequence, however, epoxy transforms into a glass-like finish.

Why Sand Epoxy Resin?

Even when poured carefully, epoxy surfaces often develop air bubbles, uneven spots, or small dust particles. Sanding removes these imperfections and creates a uniform surface that can be polished to a high gloss. The process is similar to finishing automotive paint—progressive grit refinement is key.

Tools You’ll Need

• Wet/dry sandpaper sheets
• Spray bottle with water and a drop of dish soap
• Soft sanding block or foam pad
• Microfiber towels
• Polishing compound for resin

Best Grit Sequence for Epoxy

• 400 grit (50-pack) — Removes high spots, uneven surfaces, and bubbles.
• 800 grit (50-pack) — Smooths out scratches from coarse sanding.
• 1500 grit (25-pack) — Refines the surface for clarity before polishing.
• 3000 grit (50-pack) — Final ultra-fine sanding step for a mirror-like finish.

Step-by-Step: Sanding Epoxy Resin

1. Level with 400 grit. Use 400 grit sheets with plenty of water to flatten uneven areas.
2. Refine with 800 grit. Apply 800 grit sandpaper to smooth scratches and bring back transparency.
3. Smooth with 1500 grit. Sand using 1500 grit sheets for a near-polished surface.
4. Finish with 3000 grit. Polish with 3000 grit sandpaper to achieve a flawless, glossy result.
5. Polish and seal. Use a resin polishing compound for the final shine and protection.

Special Cases

• Thick pours: May require extra time at 400 grit to flatten the surface.
• Small crafts: Sand by hand using circular motions for more control.
• Countertops: Consider using an orbital sander with fine grits for faster coverage.

Pro Tips

• Always wet sand epoxy to avoid heat buildup and clogging.
• Work slowly through each grit—don’t skip steps.
• Check progress under bright light to spot imperfections.

Aftercare

• Seal finished epoxy with a UV-resistant topcoat to prevent yellowing.
• Clean only with mild soap and water—avoid abrasives.
• Polish occasionally to maintain the shine.

FAQs

• Can I dry sand epoxy? Not recommended—wet sanding gives the best clarity and prevents clogging.
• How long should epoxy cure before sanding? At least 48–72 hours, depending on thickness and brand.
• What if the surface looks cloudy? Keep refining through finer grits and finish with polish.

Watch & Learn

Polishing epoxy resin to a mirror finish requires patience and the right grit sequence. Stock up on ultra-fine wet/dry sheets and transform your resin projects into crystal-clear masterpieces.