Grit Size

Grit Size chart
Effect on Grit Sizes for Diamond & CBN on surface finish
Effect of Grit Size on Surface Finish Diamond & CBN U.S Standard ASTM-E-11 FEPA Standard
Diamond CBN
Rough Grinding *Ra Micron (mm) 1.8-3.61
60/70 D251 B251
70/80 D213 B213
80/100 D181 B181
Medium Grinding *Ra micron (mm) 0.48-1.32
120/140 D151 B151
140/170 D126 B126
170/200 D107 B107
200/230 D91 B91
Finishing *Ra Micron (mm) 0.23-0.38
230/270 D76 B76
270/325 D64 B64
325/400 D54 B54
Super Finishing *Ra Micron (mm) 0.1 and below
500 D46 B46
600 D30-40 B30-40
800 D22-36 B22-36
1000 D15-25 B15-25
1200 D10-20 B10-20
1500 D8-16 B8-16
*Ra Micron (mm) – estimated finishing range according to grit sizes