Remove Aluminum Oxidation: 320?600?1200 Grit Sequence

Aluminum naturally oxidizes, forming a dull, chalky layer that hides its shine. Fortunately, you can restore bare aluminum to a bright finish with a simple sanding sequence: 320 ? 600 ? 1200 grit, followed by polishing. Each grit strips oxidation and smooths the surface step by step.

Why Aluminum Oxidizes

Exposure to air and moisture creates aluminum oxide on the surface. While it protects against corrosion, it dulls appearance. Sanding removes this layer, revealing the bright metal underneath. Refining grits ensure scratches from early passes disappear before final polish.

Tools & Materials

• 9×11 in wet/dry sandpaper sheets: 320, 600, 1200 grit
• Sanding block or sponge
• Spray bottle with water for wet sanding
• Microfiber cloths
• Aluminum polish or buffing compound
• Buffing pad, drill attachment, or cloth applicator
• PPE: gloves, respirator, safety glasses

Recommended Grit Sequence

• 320 grit — Removes heavy oxidation and pitting.
• 600 grit — Refines scratches, smooths surface.
• 1200 grit — Pre-polish clarity, ready for compound.

Step-by-Step: Aluminum De-Oxidizing

1. Clean first. Wash aluminum with degreaser to remove dirt and oils.
2. Sand at 320 grit. Start with 320 grit (25-pack). Sand evenly until chalky oxidation disappears and surface looks consistent.
3. Step to 600 grit. Switch to 600 grit (50-pack). Sand perpendicular to 320 scratches until surface feels smoother.
4. Final refine at 1200 grit. Use 1200 grit (100-pack) to leave a satin finish ready for polish.
5. Polish. Apply aluminum polish with a cloth or buffing pad until shine appears.
6. Protect. Coat with wax or clear sealer to slow future oxidation.

Special Cases

Heavy pitting: May require starting at 220 grit before 320 ? 600 ? 1200.
Anodized aluminum: Don’t sand—removes anodizing. Use anodized-specific cleaners.
Large panels: Use orbital sander for speed, but finish by hand to maintain uniform look.

Pro Tips

• Sand wet to control dust and prevent clogging.
• Alternate directions per grit to confirm scratch removal.
• Work evenly—uneven sanding causes waves in reflections.
• Replace sandpaper often—oxidation clogs fast.
• Seal with wax or clear coat immediately after polishing.

Aftercare

• Reapply protective coating every 3–6 months outdoors.
• Wash gently—avoid abrasives that scratch aluminum.
• For touch-ups, start at 600 ? 1200 grit, then polish again.

FAQs

• Can I skip to polish? No—oxidation is too stubborn without sanding first.
• Will sanding thin aluminum? Only slightly—work gently, just enough to remove oxidation.
• What polish works best? Aluminum-specific compounds give best results.
• Can I use power tools? Yes—but control speed and pressure to avoid gouges.

Video: Aluminum Oxidation Removal

Closing: Oxidized aluminum doesn’t mean ruined metal. With a 320 ? 600 ? 1200 grit sequence and polish, you can restore bright, reflective surfaces and keep them shining longer with proper protection.