Injection Mold Design Guide May 2026

Welcome to the definitive . Whether you are a mold engineer, a product designer, or a procurement manager, understanding the following 12 pillars of mold design will save you hundreds of thousands of dollars and months of frustration.

Before we look at specific features, we must adopt the mindset of the mold maker. An injection mold is a pressurized vessel. Typical melt pressures range from 10,000 to 30,000 PSI. Every design decision must answer one question: How does this affect melt flow and ejection? injection mold design guide

The guide told of a legendary “coughing mold”—every time it opened, a puff of dust came out. That dust was degraded polymer from hot spots caused by sudden wall thickness changes. The solution? Ribs, not thick walls. A 60% rule: ribs should be no thicker than 60% of the nominal wall. Welcome to the definitive