Edge gate

An opening aligned with the parting line of the mold where resin flows into the cavity. Edge gates are typically placed on an outside edge of the part.


Electric discharge machining. A moldmaking method which can create taller, thinner ribs than milling, text on top of ribs and square outside edges on parts.


The final stage of the injection-molding process where the completed part is pushed from the mold using pins or other mechanisms.

Ejector pins

Pins installed in the B-side of the mold that push the part out of the mold when the part has cooled sufficiently.

Elongation at break

How much the material can stretch or deform before breaking. This property of LSR allows for some difficult parts to be surprisingly removed from molds. For example, LR 3003/50 has an elongation at break of 480 percent.

End mill

A cutting tool that is used to machine a mold.


Electro static discharge. An electrical effect that may necessitate shielding in some applications. Some special grades of plastic are electrically conductive or dissipative and help prevent ESD.