The core difference
A cold runner mold forms both the plastic part and the runner during each cycle. A hot runner mold keeps the runner system heated so material can flow directly into the cavity with less runner waste.
When a cold runner mold is suitable
Cold runner tooling is often simpler and has a lower initial mold cost. It can be a good choice for lower production volume, simple products, material testing or projects where runner recycling is acceptable.
When a hot runner mold makes sense
Hot runner systems are useful for high-volume production, large parts, multi-cavity molds or materials where runner waste is expensive. They can improve cycle efficiency, but the mold cost and maintenance requirements are higher.
How buyers should compare options
Do not compare only mold price. Compare annual quantity, material cost, runner weight, cycle time, product appearance, maintenance ability and local molding machine conditions. The better choice depends on total production economics.
Information needed for a recommendation
The mold maker needs the part drawing, material, part weight target, expected quantity, cavity number and whether the mold will be exported or used for production at the supplier's factory.