How to Sand Metal for Polishing: Mirror-Like Shine

Whether it’s automotive parts, tools, or decorative metalwork, polishing starts with sanding. Proper sanding removes scratches, oxidation, and surface imperfections, paving the way for a flawless mirror finish. This guide explains the grit sequence and techniques for professional polishing results.

Why Sand Before Polishing Metal?

Polishing compounds alone cannot remove deep scratches or pitting. Sanding progressively smooths the surface, reducing defects until the metal is ready for buffing. Skipping sanding leaves swirl marks and an uneven shine.

Tools You’ll Need

• 9x11 in wet/dry sandpaper sheets
• Sanding block or orbital sander
• Water for wet sanding
• Polishing compound
• Microfiber cloths and buffing wheel

Best Grit Sequence for Metal Polishing

• 400 grit: Removes oxidation, rust stains, and initial scratches.
• 800 grit: Smooths surface further for refinement.
• 1500 grit: Pre-polish sanding for semi-gloss finish.
• 2000 grit: Creates a near-mirror base surface.
• 3000 grit: Ultra-fine sanding for the highest clarity before buffing.

Step-by-Step: Sanding Metal for Polishing

1. Clean the surface. Remove grease and dirt with a degreaser.
2. Start with 400 grit. Wet sand using 400 grit (25-pack) to eliminate oxidation.
3. Move to 800 grit. Apply 800 grit (50-pack) to refine scratches.
4. Polish with 1500 grit. Use 1500 grit (100-pack) for a smooth, pre-polish surface.
5. Finish with 2000–3000 grit. Wet sand evenly to create a flawless mirror-ready finish.
6. Buff and polish. Apply polishing compound with a buffing wheel or microfiber cloth until the surface shines.

Special Cases

For aluminum, use lighter pressure to avoid gouging. For stainless steel, work through the full grit sequence up to 3000 for best results.

Pro Tips

• Always wet sand fine grits to avoid heat buildup and clogging.
• Sand in alternating directions with each grit for even scratch removal.
• Inspect under bright light—scratches missed early will show in the polish.

Aftercare

• Apply protective wax or sealant to slow oxidation.
• Wipe metal surfaces regularly with microfiber cloths.
• Avoid harsh chemicals that dull polished finishes.

FAQs

• Can I skip straight to polishing compound? No—deep scratches must be removed with sandpaper first.
• Do I need power tools? Not always—hand sanding works, but a buffer speeds up polishing.
• Which metals polish best? Aluminum, brass, and stainless steel respond well to progressive sanding and polishing.

Watch & Learn

For flawless polishing prep, use eQualle’s wet/dry sandpaper sheets, available in 25, 50, and 100 packs. Shop polishing sandpaper here.