Identifying and Resolving Molding Defects

Learn to recognize defects like warping, sink marks, and short shots. Each flaw provides clues about underlying process issues, such as temperature imbalances or incorrect material measurements.

Warping occurs due to uneven cooling. To prevent it, maintain uniform mold temperature and cooling time. Consider material selection and mold design adjustments for optimal thermal conductivity.

Sink marks are depressions caused by inadequate cooling or filling. Counteract them by optimizing the holding pressure and time, ensuring sufficient material in cavity sections prone to sinking.

Short shots happen when the mold doesn't fill completely. To avoid this, check for proper venting, sufficient material flow, and appropriate melt temperatures. A robust injection pressure setting is also crucial.

Jetting creates snake-like patterns inside the mold cavity. This is often due to turbulent flow. Minimize jetting by adjusting the mold design for smoother material flow and optimizing gate locations.

Burn marks result from trapped air or overheating. Improve venting and reduce injection speed to allow air to escape. Monitor material degradation and adjust processing conditions accordingly.

Implement computational flow analysis to anticipate and mitigate potential defects. Using software simulations can refine gate placement, pressure controls, and cooling system design before actual production begins.