Step-by-Step Sanding with 120, 320, and 1500 Grit Sandpaper

For projects that demand smooth preparation, fine refinement, and a polished finish, the sanding sequence of 120, 320, and 1500 grit sandpaper is a proven method. This progression works across woodworking, auto body refinishing, and resin projects.

Why This Sequence Works

120 grit provides solid prep, removing minor coatings and scratches. 320 grit smooths the surface, bridging the coarse-to-fine transition. Finally, 1500 grit produces a silky, polished finish ideal for high-end results.

Tools You’ll Need

• Orbital sander or block for 120 grit prep
• Sanding sponge or pad for 320 grit refinement
• Foam pad with water spray bottle for 1500 grit wet sanding
• Vacuum and tack cloth

Step-by-Step Process

1. Surface prep. Start with 120 grit (25-pack) to level surfaces and remove light coatings or scratches.
2. Intermediate sanding. Switch to 320 grit (50-pack) to refine surfaces and prepare for finishes.
3. Final polish. Wet sand with 1500 grit (100-pack) to create silky smooth, professional-grade results.
4. Clean carefully. Vacuum and tack cloth between each sanding stage to avoid embedded dust.

Special Cases

In woodworking, 320 grit is often the final step before staining, but 1500 grit takes finishes to another level. In auto refinishing, 120 grit preps fillers, 320 smooths primers, and 1500 polishes clear coats. Resin projects also shine at 1500 grit for added clarity.

Pro Tips

• Don’t skip directly from 120 to 1500—320 grit ensures a smooth transition.
• Always wet sand at 1500 grit to prevent clogging and maximize clarity.
• Use light, even pressure with fine grits to avoid streaks.

Aftercare

• Apply sealers or finishes after sanding to preserve smoothness.
• Buff 1500 grit surfaces with compounds for mirror-like gloss.
• Store sandpapers flat and dry to extend their shelf life.

FAQs

• Is 120 grit enough for finishing? No, it’s for prep—always continue with finer grits.
• Why use 320 grit? It bridges prep sanding and fine sanding, creating a finish-ready surface.
• What’s 1500 grit best for? It polishes surfaces to silky smoothness, perfect for resin, auto, and woodworking projects.

Watch & Learn

By sanding with 120, 320, and 1500 grit sandpaper, you’ll achieve results that move smoothly from prep to polished finishing, making any project look professional.