Mold Design

The female half of a plastic injection mold. It is the interior surface that shapes the molten plastic and defines the outer geometry of the part. Typically located in the stationary platen.

The male half of a mold. It forms the interior surfaces and hollow features of the part. Typically located in the moving platen and, together with the cavity, defines the full part geometry when closed.

Design for Manufacturability (DFM) is the analysis of a part's suitability for mold tooling and plastic injection processes during the design phase. Wall thickness uniformity, draft angles, and overall part geometry are the primary elements of this analysis.

A slight taper applied to vertical surfaces of plastic injection parts to allow clean ejection from the mold. Typical values range from 1° to 3°, though textured surfaces may require greater angles.

The opening through which molten plastic passes from the runner system into the mold cavity. Gate size, location, and type (pin, tunnel, edge, etc.) directly affect fill quality and the formation of weld lines in the part.

The plane or surface where the two halves of the mold (cavity and core) separate. This line may leave a slight mark on the part; it is typically planned at an inconspicuous location or at a natural geometric boundary.

Surface depressions that form on plastic parts during cooling, caused by volumetric shrinkage in thicker cross-sections beneath the surface. Minimized by uniform wall thickness and optimized cooling channel design.

The line formed in a mold cavity where two molten plastic flow fronts coming from different directions meet. Mechanical strength and surface quality can be reduced at the junction; minimized through gate placement design.