Runners
A runner is a channel cut into custom injection molds. Plastic or resin travels from:
injection molding machine→ sprue→ runner → gate → the finished part.
Runners in molded parts
Below are examples of runners in actual molded samples.
Notes: in most of the occasion, you won’t see the runners when you receive the molded components, as mold makers cut them after molding or they may not even exist (for hot runners).
Types of Runners
There are 2 types of runners: cold runners and hot runners. Below are simple explanation to these 2 types of runners:
Cold runners:
Hot runners:
Runners in DFM Report
We will provide runner layout in our DFM report, and you will need to confirm it before tooling.
