The finest sandpaper available can reach exceptionally high grit levels, often exceeding 7000-grit for specialized polishing tasks such as automotive clear coats, jewelry, or optics. For more common delicate finishing and micro-abrasion applications, 1000-grit sandpaper is classified as ultra-fine and represents some of the most delicate abrasives used for smoothing surfaces.
Understanding Sandpaper Grit
Sandpaper grit refers to the size of the abrasive particles on the sandpaper. The grit number indicates the number of abrasive particles per square inch. A higher grit number signifies smaller, finer abrasive particles, resulting in a smoother finish. Conversely, a lower grit number indicates larger, coarser particles, ideal for aggressive material removal.
Micro Grit Sandpaper Categories
When working on projects that require an extremely smooth or polished surface, micro grit sandpaper is essential. These very fine grits are used for final sanding stages, smoothing out minor imperfections, or preparing a surface for polishing. The categories typically include:
| Grade | CAMI Grit Range | Description |
|---|---|---|
| Ultra Fine | 800 or 1000 | Considered the most delicate abrasives, ideal for achieving a super-smooth finish. |
| Super Fine | 400, 500, 600 | Slightly wipes away small inconsistencies and patches, but not strong enough for significant material removal. |
| Extra Fine | 320 or 360 | Slightly less fine and more abrasive than Super Fine, used for refining surfaces before final sanding. |
| Very Fine | 240 | The least fine of the micro abrasives, suitable for light sanding and preparing surfaces for finer grits. |
When to Use Fine Grit Sandpaper
Using fine grit sandpaper is crucial for various applications where surface perfection is key.
- Final Finishing: To achieve a silky-smooth feel on wood, plastics, or metals before applying a final coat of paint, varnish, or polish.
- Removing Minor Imperfections: Excellent for gently buffing out light scratches, scuffs, or haze from delicate surfaces.
- Automotive Detailing: Ultra-fine grits (often above 1000) are vital for wet-sanding clear coats to remove orange peel effect or minor defects, preparing the surface for compounding and polishing.
- Polishing Plastics and Acrylics: Restoring clarity to headlights or other plastic components by progressively moving to finer grits.
- Jewelry and Metal Finishing: Achieving a high-luster polish on precious metals or intricate metalwork.
When selecting sandpaper, always consider the material you're working with and the desired outcome. Beginning with a coarser grit to remove material or shape, then progressively moving to finer grits, is a standard technique for achieving the best results.
