Ground Bar Tolerances
Below we list standard ISO tolerance for precision ground, bright drawn, smooth current and polished round steel bar (diameter).
Metric Diameters
| Dia – mm |
ISO h6 |
ISO h7 |
ISO h8 |
ISO h9 |
ISO h10 |
ISO h11 |
| 1 < 3 |
0.006 |
0.010 |
0.014 |
0.025 |
0.040 |
0.060 |
| 3 < 6 |
0.008 |
0.012 |
0.018 |
0.030 |
0.048 |
0.075 |
| 6 < 10 |
0.009 |
0.015 |
0.022 |
0.036 |
0.058 |
0.090 |
| 10 < 18 |
0.011 |
0.018 |
0.027 |
0.043 |
0.070 |
0.110 |
| 18 < 30 |
0.013 |
0.021 |
0.033 |
0.052 |
0.084 |
0.130 |
| 30 < 50 |
0.016 |
0.025 |
0.039 |
0.062 |
0.100 |
0.160 |
| 50 < 80 |
0.019 |
0.030 |
0.046 |
0.074 |
0.120 |
0.190 |
| 80 < 120 |
0.022 |
0.035 |
0.054 |
0.087 |
0.140 |
0.220 |
| 120 < 180 |
– |
– |
0.063 |
0.100 |
0.160 |
0.250 |
| 180 < 250 |
– |
– |
0.072 |
0.115 |
0.185 |
0.290 |
| 250 < 275 |
– |
– |
0.081 |
0.130 |
0.210 |
0.320 |
Imperial Diameters
| Dia – inches |
ISO h6 |
ISO h7 |
ISO h8 |
ISO h9 |
ISO h10 |
ISO h11 |
| 0.039 < 0.118 |
0.00025 |
0.0004 |
0.0006 |
0.0010 |
0.0016 |
0.0024 |
| 0.118 < 0.236 |
0.0003 |
0.0005 |
0.0007 |
0.0012 |
0.0019 |
0.0030 |
| 0.236 < 0.393 |
0.0004 |
0.0006 |
0.0009 |
0.0014 |
0.0023 |
0.0035 |
| 0.393 < 0.707 |
0.0004 |
0.0007 |
0.0010 |
0.0016 |
0.0028 |
0.0043 |
| 0.707 < 1.181 |
0.0005 |
0.0008 |
0.0012 |
0.0020 |
0.0035 |
0.0051 |
| 1.181 < 1.969 |
0.0006 |
0.0010 |
0.0016 |
0.0025 |
0.0040 |
0.0063 |
| 1.969 < 3.150 |
0.0007 |
0.0012 |
0.0018 |
0.0030 |
0.0046 |
0.0075 |
| 3.150 < 4.724 |
0.0009 |
0.0014 |
0.0022 |
0.0035 |
0.0055 |
0.0087 |
| 4.724 < 7.087 |
– |
– |
0.0025 |
0.0039 |
0.0063 |
0.0098 |
| 7.087 < 9.843 |
– |
– |
0.0028 |
0.0045 |
0.0073 |
0.0114 |
| 9.843 <10.827 |
– |
– |
0.0031 |
0.0051 |
0.0083 |
0.0126 |
