The Right Sanding Progression for Smooth Finishes

Sanding determines whether your finish looks professional or amateur. Here’s how to achieve glass-smooth surfaces without spending hours fighting scratches.

Start Coarse, End Fine

Begin with the lowest grit that removes tool marks—usually 80 or 100 for rough surfaces, 120 for cleaner stock. Never skip more than one grit level. Jump from 80 to 180 and you’ll spend more time removing 80-grit scratches than you saved by skipping 120.

The Progression That Works

For most projects: 120, 150, 180, 220. Stop at 220 for painted pieces. Oil finishes and waterborne products benefit from going to 320. Film finishes like lacquer and polyurethane rarely need finer than 220—the finish builds over minor imperfections.

Technique Matters

Sand with the grain, never across it. Cross-grain scratches highlight under finish. Use a sanding block for flat surfaces—fingers alone create dips and waves. Apply even pressure without bearing down hard. Let the abrasive work.

Spot the Scratches

Use raking light at a low angle to reveal remaining scratches before moving to finer grits. Wiping with mineral spirits temporarily shows what the final finish will reveal. Fix problems now, not after applying stain that makes scratches obvious.

Between Coats

Lightly sand between finish coats with 320 or 400 grit. You’re knocking down dust nibs and providing tooth for the next coat, not reshaping the surface. Wipe away all dust before recoating.

Good sanding separates professional results from amateur work. Invest the time here and your finishes will look noticeably better.