How to Sand Resin and Epoxy Projects for a Glass-Like Finish (120, 220, 320, 400, 600, 1000, 1500, 2000, 3000 Grit Complete Guide)

Resin and epoxy are popular for river tables, jewelry, countertops, and art projects. Their glossy, glass-like finish makes them stunning, but achieving that clarity requires careful sanding and polishing. This guide explains how to move through grits 120, 220, 320, 400, 600, 1000, 1500, 2000, and 3000 to transform cloudy resin into a mirror surface.

Why Sanding Resin Matters

Resin pours often cure with imperfections such as waves, bubbles, or uneven surfaces. Sanding ensures:

• Leveling: Removes ridges, bumps, and dust nibs.
• Clarity: Polishing restores transparency for a glass-like look.
• Durability: Proper sanding ensures finishes won’t peel or haze prematurely.
• Professional results: Elevates handmade projects to showroom quality.

Grit Sequence Explained

• 120 grit: For leveling thick epoxy pours or removing surface defects.
• 220 grit: Smooths scratches from coarse sanding.
• 320 grit: Refines surface texture before fine sanding.
• 400 grit: Creates a pre-polish surface.
• 600 grit: Begins clarity restoration—haze reduces significantly.
• 1000 grit: Key step for smooth transparency.
• 1500 grit: Removes micro scratches before polishing.
• 2000 grit: Leaves resin nearly clear.
• 3000 grit: Final sanding before buffing compounds.

Tools You’ll Need

• Wet/dry sandpaper: For all stages, especially above 400 grit.
• Spray bottle: Water lubrication prevents clogging.
• Sanding block: For flat surfaces like tables or coasters.
• Orbital sander: Saves time on large surfaces.
• Polishing compound: Restores final glass-like shine.
• Microfiber cloths: For drying and buffing.

Step-by-Step Resin Sanding

1. Level with 120 grit. Flatten imperfections with 120 grit (50-pack).
2. Smooth with 220 grit. Refine surface using 220 grit (25-pack).
3. Refine further with 320 grit. Use 320 grit (100-pack) for even texture.
4. Pre-polish sanding (400 grit). Apply 400 grit (25-pack).
5. Wet sand with 600 grit. Switch to 600 grit (50-pack) for haze removal.
6. Clarity step (1000 grit). Smooth with 1000 grit (50-pack).
7. Fine sanding (1500 grit). Use 1500 grit (25-pack) to prep for gloss.
8. Near-polish (2000 grit). Sand with 2000 grit (50-pack).
9. Final sanding (3000 grit). Finish with 3000 grit (25-pack).
10. Buff & polish. Apply compound with a microfiber pad for a glass-like finish.

Special Cases

River tables: Large surfaces benefit from orbital sanders at 120–400 grit before hand-sanding finer grits.

Jewelry: Hand-sand carefully—avoid over-sanding small pieces.

Epoxy countertops: Use waterproof backing pads for even results.

Pro Tips

• Always wet sand above 400 grit—this reduces clogging and heat damage.
• Sand in alternating directions between grits to track progress.
• Don’t rush—skipping grits leaves visible scratches.
• Buff with plastic polish for extra depth and shine.

Aftercare

• Keep resin projects away from direct sunlight to avoid yellowing.
• Clean with mild soap and water, not harsh chemicals.
• Re-polish periodically to maintain shine.

FAQs

• Why is my resin cloudy after sanding? It’s normal until the final polish after 3000 grit.
• Can I skip to 2000 grit? No—scratches remain if intermediate steps are skipped.
• Is a polishing machine necessary? Not required, but it speeds up final buffing.
• How long does sanding take? Depending on project size, anywhere from 30 minutes to several hours.

Watch & Learn

Shop resin sanding sheets: From 120 grit leveling to 3000 grit polishing, available in 25, 50, and 100 packs. Shop resin sanding sandpaper.

Closing Thoughts

Sanding resin and epoxy is all about patience and progression. By working through 120 to 3000 grit, you’ll achieve a flawless surface ready for display. Whether it’s a river table centerpiece, an epoxy bar top, or a pendant, the right grit sequence ensures professional, crystal-clear results every time.