Grit and Microgrit Grading Conversion Chart
|
Grit |
Mesh |
Microns |
Inches |
|
USS** |
(Average) |
(Average) | |
| 4 | 3.5 | 5600~4750 | 0.187 (nom.) |
| 5 | 4 | 4750~4000 | 0.157 |
| 6 | 5 | 4000~3350 | 0.132 |
| 7 | 6 | 3350~2800 | 0.111 |
| 8 | 7 | 2210 | 0.087 (av.) |
| 10 | 8 | 1854 | 0.073 |
| 12 | 10 | 1600 | 0.063 |
| 14 | 12 | 1346 | 0.053 |
| 16 | 14 | 1092 | 0.043 |
| 20 | 16 | 940 | 0.037 |
| 24 | 20 | 686 | 0.027 |
| 30 | 25 | 559 | 0.022 |
| 36 | 30 | 483 | 0.030 |
| 46 | 40 | 356 | 0.014 |
| 54 | 45 | 305 | 0.012 |
| 60 | 50 | 254 | 0.010 |
| 70 | 60 | 203 | 0.008 |
| 80 | 70 | 165 | 0.0065 |
| 90 | 80 | 145 | 0.0057 |
| 100 | 100 | 122 | 0.0048 |
| 120 | 120 | 102 | 0.0040 |
| 150 | 140 | 89 | 0.0035 |
| 180 | 170 | 76 | 0.0030 |
| 220 | 200 | 63 | 0.0025 |
|
Micro Grit* |
Mesh |
Microns |
Inches |
| 240 | 200 | 50- 53.5 | 0.00200 |
| 280 | 40.5- 44.0 | 0.00154 | |
| 320 | 32.5- 36.0 | 0.00122 | |
| 360 | 25.8- 28.8 | ||
| 400 | 20.6- 23.6 | 0.00087 | |
| 500 | 16.7- 19.7 | 0.00075 | |
| 600 | 13.0- 16.0 | 0.00063 | |
| 700 | 0.00055 | ||
| 800 | 9.8- 12.3 | 0.00047 | |
| 900 | 0.00035 | ||
| 1000 | 6.8- 9.3 | 0.00028 | |
| 1200 | 4.5- 6.5 | ||
| CF1 | 48 | 0.00189 | |
| F | 40 | 0.00160 | |
| FF | 33 | 0.00130 | |
| FFF (Coarse) | 25 | 0.00099 | |
| FFF | 19 | 0.00075 | |
| FFFF | 11 | 0.00043 |
On a "best efforts basis", the above conversions are approximate and admit of the usual commercial variations