| Cracking, Crazing | |
| Possible Cause | Suggested Remedy |
| Packing excessive material into the mould | a. Decrease packing pressure b. Decrease shot size c. Increase transfer position (to lower injection peak pressure) d. Decrease injection time |
| Non-uniform or too cold a mould temperature | a. Increase mould temperature b. Supply uniform cooling to the cavity |
| Knockout system poorly designed | Redesign knockout system for balanced ejection forces |
| Inadequate draft angles or excessive undercuts | Rework mould |