Two quite different things are called printed injection tooling. One is a resin insert that runs a few dozen shots to get moulded parts within days. The other is a printed metal insert with cooling channels that follow the part surface, used in production tools to cut cycle times. They share a name and almost nothing else.
Printed resin inserts
A high temperature photopolymer insert is printed, fitted into a standard mould base and shot on a normal machine. It survives tens of shots, sometimes into the low hundreds with a forgiving resin, before it degrades. The appeal is speed: real moulded parts in the real material within days, with no machining. The limits are tool life, cycle time and the resins that can be run.
Printed metal inserts and conformal cooling
Here the printed insert is a production component. Cooling channels follow the contour of the cavity rather than being drilled straight, so heat is removed evenly and quickly. That shortens cycle time, reduces warp and improves dimensional consistency. On a high volume tool the saved seconds per cycle can repay the insert within months, which is the strongest production case for metal printing anywhere.
What each is for
Resin inserts are a prototyping and bridging tactic, competing with aluminium soft tooling on lead time. Printed metal inserts are a production optimisation, competing with conventional inserts on cycle time. Confusing them leads to disappointment in both directions: expecting production life from a resin insert, or expecting a metal insert to be quick and cheap.
Practicalities
Resin inserts need low pressure, low temperature resins, generous draft and patient cycles, and they wear visibly as they go, so parts drift. Metal inserts need the same post processing as any printed metal part, plus polishing of the cavity surface, and the cooling circuit has to be designed for pressure drop as well as for coverage. Neither is a drop in replacement for a conventional insert.
Questions people ask about 3d printed injection mold
Can you 3D print an injection mould?
You can print inserts. Resin inserts run tens of shots for prototyping. Printed metal inserts with conformal cooling are used in production tools to cut cycle time.
How many shots does a printed resin insert last?
Tens, sometimes into the low hundreds with a forgiving resin and a patient cycle. It degrades visibly as it goes, so dimensions drift.
What is conformal cooling?
Cooling channels that follow the contour of the cavity rather than being drilled straight, which removes heat faster and more evenly and shortens the cycle.
Is printed tooling cheaper?
Resin inserts are cheaper and faster than machined soft tooling for very small quantities. Printed metal inserts are more expensive than conventional ones and pay back through cycle time.