Form
Belts
Grit
60-120 assorted
Material
aluminum oxide
The verdict
Where this pick fits.
3M Pro Grade aluminum oxide on the most common bench belt size. The assortment that takes a workpiece from rough to finished without reaching for a different sander.
The common size. The assortment that covers every pass.
Quick take
- Best for: 3×21 belt sanders, general woodworking, edge sanding
- Format: Belts
- Tier: Budget tier
- Grit lane: 40, 60, 80, 100, 120
Use it when
The fit is obvious.
- · Reach for the 3M 3×21 Belt Assortment when the job is 3×21 belt sanders, general woodworking, and edge sanding: that is the fight it was built for.
- · Aluminum oxide is the reliable one: cheap, tough, no surprises and no complaints. It will outlast your patience before it outlasts the job.
- · This is the working middle: enough bite to matter, refined enough to leave the job somewhere worth continuing.
Skip it when
The job asks for something else.
- · Leave it if you are actually solving a different stage of the climb than the one this pick was chosen for.
- · Leave it if longevity and cut speed matter more than the price: cheap abrasive is cheap for reasons you feel on the tenth sheet.
- · Leave it if the surface is already close to finished: a belt will happily undo good work.
Best for
Where it earns its keep.
- · 3×21 belt sanders
- · general woodworking
- · edge sanding
Keep moving
Useful next clicks.
Buyer questions
The practical questions.
What is the 3M 3×21 Belt Assortment actually good at?
3M Pro Grade aluminum oxide on the most common bench belt size. The assortment that takes a workpiece from rough to finished without reaching for a different sander. In short: it earns its keep on 3×21 belt sanders, general woodworking, and edge sanding.
Is 60-120 assorted the right grit lane for this?
It sits closest to 40 grit, 60 grit, 80 grit, 100 grit, and 120 grit. This is a cutting stage, not a finish stage. Use it to remove material, not to fake smoothness.
What should you put it up against before buying?
Put it against other belts in the same price band doing the same job: that is where speed, finish, and cost-per-use sort themselves out.
Rough start. Smooth finish. The gap between is where the work happens.
Next step
Go deeper.
House rule
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