Draft angles: hidden geometry of injection molding
Products aren't always designed with perfectly vertical walls.
Though seemingly minor, draft angles are instrumental to injection molding. Slight tapers to walls facilitate easy removal from a mold.
This constraint can be an opportunity for affecting how light reflects off a surface, adding a dynamic element or guiding user hands. But certain products do demand perfectly straight vertical walls for their intended function.
The LEGO brick is a clever example. The draft angle isn't on the external wall, it's on the inside. This creates a perfectly vertical exterior while ensuring smooth mold release. This, along with maintaining tight tolerances, required careful precision and fine-tuning.
Problem solving for draft angles extends beyond injection molding. Any process involving molds, casting, thermoforming or certain 3D printing methods necessitates draft angle considerations. Industrial Design excels when it seamlessly marries user experience with the practical realities of production.
