Trim die

Where it comes up

• Zinc and aluminum die castingMolten zinc or aluminum injected into steel dies at high pressure. Thin walls and net shape at 2,500+ parts a year.
• ForgingClosed-die and open-die forgings in carbon, alloy, and stainless steel and aluminum, with grain flow for strength.

Related terms

Flash

Flash is excess material that escapes past the parting line or between die halves and hardens as a thin fin on the part. In molding and die casting it signals worn tooling, low clamp force, or excess pressure. In forging, flash is designed in on purpose, then trimmed off.

Closed-die forging

Closed-die forging is a forging process that presses or hammers heated metal between two shaped dies until it fills the die impression. It produces near-net parts with continuous grain flow and high fatigue strength, such as connecting rods, yokes, and wrench bodies. Excess metal escapes as flash and is trimmed.

Gate

A gate is the opening where molten plastic or metal enters the mold cavity from the runner. Gate type, size, and location affect fill, knit lines, sink, and the mark left on the part. Common types include edge, submarine, pin point, and valve gates.