Fix Silicone Fisheyes: Sand-Out & Refinish Plan

Few finish defects are as maddening as fisheyes—those tiny craters that open up as your coat levels, caused by silicone or other surface contaminants that repel finish. The good news: you can rescue the project. This guide lays out a clear, sanding-first recovery plan so you remove the defect cleanly, reset the surface, and lay down a flawless new coat.

Why Sanding Matters for Fisheyes

Fisheyes happen when a contaminant (often silicone from polishes, lubricants, or body-care products) lowers surface energy so the finish pulls back. Adding more finish usually magnifies the crater. The reliable fix is to stop, cure, sand flat, decontaminate, and then recoat. Sanding levels the crater lips and erases the telegraphed rings; done in a disciplined grit ladder, it restores a uniform scratch field that fresh finish will wet consistently.

Tools & Materials

• Random-orbit sander (RO) with soft interface pad for gentle, even pressure
• 9×11 in silicon carbide wet/dry sheets: 400–2000 grits
• Hard sanding block and foam pad for edges and profiles
• Raking light or strong side lighting for inspection
• Vacuum with brush head, microfiber cloths, tack cloth (non-oily)
• Solvent for decontamination (per finish system): naphtha, isopropyl alcohol, or manufacturer-recommended silicone remover
• Finish system for recoat (varnish, polyurethane, lacquer, automotive clear, etc.)
• PPE: respirator, eye protection, gloves

Recommended Grit Sequence

• 600 grit — Initial cut to flatten crater lips without digging through healthy film.
• 1000 grit — Refines 600 scratches and tightens the field for clear topcoats.
• 2000 grit — Optional final refine before polishing or ultra-thin recoats.

Step-by-Step: Sand-Out Protocol

1. Let the coat cure. Don’t sand soft film—crater edges will smear. Wait per label until the finish sands to powder, not gum.
2. Map the defects. Under raking light, mark fisheye zones with a wax pencil. If they’re isolated, you can spot-level and blend; if widespread, plan a full-panel refinement.
3. Decontaminate lightly. Wipe the surface with a compatible solvent (e.g., naphtha for many oil/varnish systems, IPA for some waterbornes). This removes topical silicone so sanding dust doesn’t push it around. Allow to flash off.
4. Level with 600 grit. Using a block on flats and a soft pad on contours, sand in overlapping passes until each crater disappears and the surface is uniformly matte. For dependable control at this stage, use 600 grit (25-pack) — it cuts cleanly while minimizing accidental cut-through.
5. Clean and re-check. Vacuum, wipe with a clean microfiber, and inspect again under raking light. Any remaining dimples need more 600—don’t advance grits until they’re gone.
6. Refine to 1000 grit. Step up to 1000 grit (50-pack) to erase 600’s trails. Work lightly; your goal is a tight, even scratch field that won’t telegraph through thin recoats.
7. Optional 2000 grit polish-ready pass. For high-gloss, ultra-thin, or automotive clears, make a brief pass with 2000 grit (100-pack). Stop as soon as the surface is uniformly refined; over-sanding can thin the film.
8. Final decontamination. Vacuum again and wipe with fresh solvent as allowed by your finish system. The water-break test should show clean sheeting (no beading). If beading persists, there’s still contamination—repeat the wipe and a light 1000-grit scuff.
9. Recoat smart. Apply your next coat per label. Maintain a wet edge and avoid heavy passes—thin, even coats reduce the chance of trapping pockets of contamination.
10. Inspect, then finish schedule. After the recoat flashes/cures, re-check under raking light. If perfect, proceed with your normal build, denibbing lightly as needed.

Special Cases

Fresh contamination from silicone sprays/polishes: If a room was recently sprayed with silicone lubricant or furniture polish, airborne mist can settle on your surface. Pause finishing, deep-clean surrounding areas, run air filtration, and change rags before returning to the project.
Auto clear coat fisheyes: Many paint systems allow fisheye eliminator additives. Use only if your system approves; sanding out and re-spraying is still the most reliable fix. Grits typically run 1500–3000 before compound if you’re leveling cured clear.
Wood pores holding silicone: Open-pore woods (oak/ash) can trap contaminants. After initial 600 cut, scrub with a stiff-bristle brush and solvent, then re-sand 600?1000 to reset the field.

Pro Tips

• Change paper early—dull sheets polish instead of cutting, leaving hidden rings that reappear after recoating.
• Use a soft interface pad on curves to prevent divots; a hard block on flats keeps panels dead level.
• Control your environment: isolate silicone sources (sprays, tire dressings, hand lotions), and run dust extraction to keep rogue particles off wet film.
• Always perform a water-break test before recoating; beading signals remaining contamination.
• For ultra-gloss, stop at 1000 before a fresh coat; save 2000+ for post-cure leveling and polish.

Aftercare

• Avoid silicone products in the finishing area—no aerosol polishes or lubricants during finishing week.
• Handle with clean, lint-free gloves as your film cures; fingerprints can carry contaminants.
• Between coats, store pieces in a clean, covered zone to keep airborne oils off the surface.
• For automotive panels, keep the vehicle away from silicone tire dressings until final cure.

FAQs

• Can I brush more finish over fisheyes to fill them? Usually makes it worse. Stop, cure, sand flat, decontaminate, then recoat.
• Is a fisheye additive a cure-all? No—use only in systems that specify it. Overuse can weaken the film or cause other defects.
• What if I sand through? Feather the edge, spot-seal if needed (e.g., shellac for wood), then rebuild film. Work carefully at edges where film is thin.
• Do I need to wet-sand? Optional. Wet-sanding 1000–2000 reduces clogging and yields a finer finish, but keep water away from moisture-sensitive substrates and edges.
• How do I prove the surface is clean? Water should sheet uniformly, rags should slide without slick spots, and a test patch of finish should lay without dimples.

Video: See the Sand-Out & Recoat

Closing: Fisheyes are a surface-energy problem—but sanding is your reset button. Level the crater lips with 600, tighten to 1000, optionally refine to 2000, decontaminate thoroughly, and recoat in controlled conditions. Follow this workflow and you’ll turn a ruined coat into a flawless finish.