Sandpaper Grit Guide: How to Choose the Right Abrasive for Every Job

Why Sanding Matters

Sanding is the foundation of any great paint, stain, or finish job. It removes imperfections, opens the grain of wood for better absorption, scuffs glossy surfaces for adhesion, and smooths between coats for a professional result. Using the wrong grit — too coarse or too fine — can ruin a surface or waste hours of work.

Understanding Sandpaper Grit Numbers

Grit refers to the number of abrasive particles per square inch. The lower the number, the coarser the abrasive and the more material it removes. The higher the number, the finer the abrasive and the smoother the finish.

Sandpaper Formats

Sheets

The most versatile format. Can be cut to size, folded, or wrapped around a sanding block. Available in all grits. Best for hand sanding flat and curved surfaces.

Sanding Discs

For use with random orbital sanders. Hook-and-loop (Velcro) backing makes changing discs fast and easy. Available in 5" and 6" diameters for most sanders.

Sanding Belts

For belt sanders. Ideal for rapid material removal on large flat surfaces like floors, decks, and tabletops.

Sanding Sponges

Flexible foam-backed abrasives that conform to curved and irregular surfaces. Great for moldings, spindles, and contoured furniture. Can often be rinsed and reused.

Sanding Rolls

Continuous rolls that can be cut to any length. Convenient for wrapping around dowels, pipes, and custom sanding blocks.

Wet/Dry Sandpaper

Silicon carbide paper that can be used wet or dry. Wet sanding with water or lubricant produces an ultra-smooth finish and reduces dust. Essential for automotive finishing and between-coat sanding on high-gloss finishes.

Sandpaper Materials

• Aluminum Oxide — the most common; durable, self-sharpening, works on wood, metal, and paint. Best all-purpose choice.
• Silicon Carbide — harder and sharper than aluminum oxide; ideal for wet sanding, metal, and hard materials
• Garnet — natural abrasive; softer and less durable but produces a fine finish on wood; preferred by some woodworkers for final sanding
• Ceramic — extremely durable; best for heavy material removal on metal and hardwood with power tools
• Zirconia — aggressive cutting action; ideal for metal grinding and heavy stock removal

Sanding Sequence: How to Sand Like a Pro

1. Start with the right grit — assess the surface condition. Rough or painted surfaces start at 80–100 grit; already smooth surfaces start at 120–150.
2. Never skip more than one grit — jumping from 80 to 220 leaves deep scratches that show through the finish. Progress through grits systematically.
3. Sand with the grain — on wood, always sand in the direction of the grain to avoid cross-grain scratches
4. Use consistent pressure — let the abrasive do the work; excessive pressure causes uneven sanding and premature wear
5. Clean between grits — remove all dust with a tack cloth or vacuum before moving to the next grit
6. Finish at 180–220 for paint — this is the ideal final grit before applying primer or paint
7. Sand between coats — lightly sand with 220–320 grit between paint coats for a smooth, professional finish

Pro Tips

• Wrap sandpaper around a sanding block for flat surfaces — it distributes pressure evenly and prevents finger grooves
• Use a sanding sponge for curved surfaces and moldings — it conforms to the shape better than rigid blocks
• Fold sandpaper in thirds for hand sanding — it gives you three fresh surfaces before the paper is worn out
• Check your work with a raking light — hold a light at a low angle to the surface to reveal scratches and imperfections

Shop Sandpaper & Abrasives

Find the right grit for every stage of your project in our Sandpaper & Abrasives collection at ProFix Home Repair.