Sheets
Pro
Grit · 80
Norton 3X Sheet Sandpaper, 80 Grit (20-pack)
When 100-grit has been disappointing you and you're done being patient.
Norton (Saint-Gobain) · Line profile
Norton 3X sandpaper, decoded.
European numbers on an American shelf.
Norton 3X is the hardware-store sheet that woodworkers stop arguing about once they’ve used it. The grain is heat-treated aluminum oxide, the coat is open with a water-based stearate dressing to resist loading, and the sheets are 9 by 11 inches like everything else on the rack.
The detail that matters for this page: 3X is P-graded. Next to CAMI-marked paper with the same number, a 3X P220 is a twin, but a 3X P320 is noticeably coarser than a CAMI 320 and a 3X P400 sits nearer a CAMI 320 than a 400. Mix brands mid-climb and that is where the stray scratch comes from.
- Mineral
- Heat-treated aluminum oxide
- Grading
- FEPA P-grade
- Coating
- Open coat, water-based stearate
- Sheets
- 9″ × 11″, P60–P400
The chart
Norton 3X in microns and CAMI.
| 3X grade | Size · nearest CAMI |
|---|---|
| P60Flattening rough stock, stripping old finish. | ~269 µm · ≈ 60 CAMI |
| P80The first real pass on most furniture.Norton 3X 80-Grit Sandpaper → | ~201 µm · ≈ 80 CAMI |
| P100Cleaning up the 80 scratch on softwoods. | ~162 µm · ≈ 80–100 CAMI |
| P120The everyday middle; most paint prep stops here.Norton 3X 120-Grit Sandpaper → | ~125 µm · ≈ 120 CAMI |
| P150Pre-primer smoothness. | ~100 µm · ≈ 150 CAMI |
| P180Hardwoods before stain. | ~82 µm · ≈ 180 CAMI |
| P220Last step before finish; scuffing between coats.Norton 3X 220-Grit Sandpaper → | ~68 µm · ≈ 220 CAMI |
| P320Between coats of poly or lacquer. | ~46.2 µm · ≈ 240–320 CAMI |
| P400Fine between-coat work on finish. | ~35 µm · ≈ 320 CAMI |
Grade range, mineral and coating are from Norton 3X distributor listings. Micron and CAMI columns are computed from the published CAMI/FEPA table; where a P-grade lands between two CAMI grades, both are shown.
Another brand's numbers to match? The grit converter lines up P-grades, CAMI, microns and Trizact A-grades.
Sources: Coastal Tool: Norton 3X abrasive sheets · Tools for Working Wood: Norton 3X · CAMI / FEPA table (Wikipedia rev. 1127917881)
Norton 3X vs 3M Pro Grade
Both are aluminum oxide hand sheets with an anti-clog coat, and both are good. The difference worth knowing is the number: 3X is P-graded, so a climb that mixes the two brands above 220 is not the climb you think it is. Pick one brand for the finishing grits. Our head-to-heads: 3X 220 vs Pro Grade assorted and 3X 80 vs 3M 40.
In the catalog
Every Norton 3X SKU we cover.
Sheets
Pro
Grit · 120
Norton 3X Sheet Sandpaper, 120 Grit (20-pack)
120. The grit that decides whether the job goes well or badly.
Sheets
Pro
Grit · 220
Norton 3X Sheet Sandpaper, 220 Grit (20-pack)
Where rough gives way to something worth running your fingers across.
Questions people ask
Is Norton 3X ceramic?
No. Norton describes 3X as premium heat-treated aluminum oxide. Norton’s ceramic lines are sold under other names.
Is Norton 3X P-graded or CAMI?
P-graded (FEPA). Up to 220 that matches CAMI paper with the same number; above it, a P320 or P400 3X sheet is coarser than a CAMI sheet with the same digits.
What grits does Norton 3X come in?
Distributors list 9 by 11 inch sheets in P60, P80, P100, P120, P150, P180, P220, P320 and P400.