Dustances between holes and distances of hole from side wall
| Hole diameter /mm | Minimum distance from edge /mm | Minmum distance from each other /mm |
| 1.6 | 1.6 | 3.6 |
| 2.4 | 2.8 | 4.8 |
| 3.2 | 4.0 | 6.4 |
| 4.8 | 5.5 | 7.9 |
| 6.4 | 6.4 | 11.0 |
| 7.9 | 7.9 | 14.0 |
| 9.5 | 8.7 | 22.2 |
| 12.7 | 11.1 | 22.2 |
For blind hole, if the wall at the bottom of the holeis less than 1/6 the diameter of the hole, the bottom will tend to bulge after molding as shown in Fig.2.27b and can not to obtain a desired designed workpiece as Fig2.27a. A better design is shown in Fig2.27c, and to keep hole proportions uniform throughout, and there are no sharp corners for stress concentrations to occur.
