3" x 21" Sanding Belts
3" x 21" Aluminum Oxide Sanding Belts
USA1 Abrasives 3" x 21" Sanding Belts are one of the most common portable belt sander sizes, used widely in woodworking shops, job sites, and metalworking environments. Semi-open coat aluminum oxide on X-weight cloth backing delivers fast, consistent stock removal with excellent clog resistance. Sold in packs of 10 belts.
Technical Specifications
- Abrasive Material: Aluminum oxide
- Coat Type: Semi-open coat
- Backing: X-weight cloth
- Bond Type: Resin-over-resin
- Belt Size: 3" x 21"
- Direction: Bidirectional
- Package Size: 10 belts per pack
- Available Grits: 36, 40, 50, 60, 80, 100, 120, 150, 180
Key Features & Benefits
- Semi-Open Coat: Resists loading for longer belt life
- X-Weight Cloth Backing: Handles belt tension and heat without stretching or tearing
- Bidirectional: Runs in either direction for easy installation
- Wide Grit Range: 36–180 grit covers aggressive removal through fine finishing
- Versatile: Works on wood, metal, plastic, and composites
Recommended Applications
- Portable belt sanding on wood and metal
- Stock removal and surface leveling
- Paint and finish stripping
- Edge sanding and shaping
- Metal deburring and surface preparation
Grit Selection Guide
- 36-50 Grit: Aggressive stock removal and shaping
- 60-80 Grit: General smoothing and surface preparation
- 100-120 Grit: Fine sanding before finishing
- 150-180 Grit: Final finishing and between-coat sanding
The Most Common Portable Belt Size. Full Grit Range. Reliable Performance.