Sanding Resin Projects: From Casting Prep to High-Gloss Polish

Epoxy resin projects—from jewelry to tabletops—require careful sanding to remove imperfections and bring out a glass-clear shine. Because resin is softer than wood or metal, using the correct grit sequence is essential to avoid scratches and cloudiness. This guide explains the full process, from initial leveling to the final polish.

Why Sanding Resin Matters

Fresh resin often cures with uneven surfaces, bubbles, or sharp edges. Sanding levels the surface, removes blemishes, and creates the foundation for polishing. Skipping or rushing grit stages leaves haze or visible scratches that polishing alone can’t fix.

Tools You’ll Need

• Wet/dry silicon carbide sandpaper sheets
• Soft sanding block or orbital sander
• Water spray bottle or bucket for wet sanding
• Polishing compound and microfiber cloths
• Protective mask and gloves

Recommended Grit Sequence

• 400 grit: Level uneven resin surfaces and remove bubbles.
• 800 grit: Refine scratches and smooth surface (800 Grit (25-pack)).
• 1500 grit: Begin polishing stage (1500 Grit (50-pack)).
• 3000 grit: Final wet sanding for ultra-clear shine (3000 Grit (100-pack)).

Step-by-Step: Sanding Resin

1. Clean the piece. Wash resin with mild soap and water, then dry completely.
2. Start with 400 grit. Wet sand lightly to remove uneven spots and high points.
3. Progress to 800 grit. Smooth surface further, sanding evenly with light pressure.
4. Move to 1500 grit. Wet sand to reduce haze and prepare for polishing.
5. Finish with 3000 grit. Sand gently until the resin appears uniformly smooth and slightly cloudy.
6. Polish. Apply resin polish with a microfiber cloth or buffing pad to achieve a glass-like finish.

Special Cases

For deep-pour tabletops, begin with coarser sanding (220–320 grit) before following the standard sequence. Small resin jewelry often only requires 800–3000 grit and polish.

Pro Tips

• Always wet sand to prevent resin dust, which can be irritating.
• Sand in small, overlapping motions for consistency.
• Check progress often by drying the piece between grit stages.

Aftercare

• Protect polished resin from direct sunlight to prevent yellowing.
• Re-polish as needed to maintain clarity.
• Clean with soft, non-abrasive cloths only.

FAQs

• Can I use a power sander on resin? Yes, but use light pressure and fine grits to avoid swirl marks.
• Do I need to re-pour resin if sanding reveals bubbles? No, you can sand them out and polish smooth.
• Is buffing compound necessary? Yes—sanding prepares the surface, but polishing compound restores full clarity.

Watch & Learn

With the right sanding sequence, resin projects can achieve a crystal-clear finish. Stock up on super fine sanding sheets to keep your resin work looking flawless.