3D‑Printed Molds for Low‑Volume Injection Molding – Download the IPC Technical Study

The French Industrial Technical Center for Plastics and Composites (IPC) completed a two‑year research project to evaluate the feasibility of 3D‑printed molds for low‑volume injection molding. The report documents the fabrication steps, injection trials, and best‑practice guidelines for molds produced with Formlabs solutions.

Why 3D‑Print Injection Molds?

Injection molding delivers high‑quality, repeatable plastic parts at a fraction of the cost of other manufacturing methods. Yet the steep price of traditional steel tooling can make it difficult to launch small‑batch or prototype programs. 3D‑printed injection molds give engineers, manufacturers, and designers a cost‑effective, rapid‑turnaround alternative that supports functional prototypes, pre‑production runs, and limited‑series production.

Find out more about injection molding costs in our in‑depth guide.

Research by IPC – A Leader in Plastics and Composites

IPC is France’s premier Industrial Technical Center focused on plastic and composite innovation. By partnering with European research leaders, IPC supports small‑ and medium‑sized enterprises with R&D expertise, technology transfer, and circular‑economy solutions. Three flagship programs—DIS 30 (circular economy), PRINTER (additive manufacturing), and HYPROD 2 (high‑value products)—enable companies to prototype, test, and commercialize new products efficiently.

As part of its ongoing research agenda, IPC examined the viability of injection molding with 3D‑printed molds, concentrating on Formlabs 3D printers in this study.

Study Details and Benchmark Geometries

The IPC project unfolded over two years and was divided into three distinct phases:

1. Comparison of 3D‑Printing Technologies: IPC collected technical data from multiple manufacturers, assessing thermal and mechanical properties via heat deflection temperature (HDT) and Young’s modulus. Four benchmark geometries were printed across each technology to identify the most promising materials. Resin‑based printers emerged as the optimal choice for injection molds, offering high resolution and smooth surface finish.

Across all evaluated technologies, dimensional variation was similar: ±0.02–0.05 mm for small features and ±0.05–0.20 mm for larger dimensions. For context, a machined metal tool typically achieves ±0.02 mm precision, which is essential for a clean parting line and minimal flashing. IPC proposes two methods to optimize the parting line in polymeric tools.

Benchmark geometries.

2. Material Characterization, Design, and 3D‑Printing Guidelines

3. Injection Trials: IPC conducted two trials using different mold sets. The first trial employed a “torture‑test” design, injecting nearly a hundred polypropylene parts with a mono‑material mold printed in Formlabs High‑Temp Resin. The second trial used a more demanding “torture‑test” design, producing thousands of polypropylene parts with a multi‑material mold: core and inserts printed in Formlabs Rigid 10K Resin, and the frame fabricated in PA12 via SLS.

Our white paper focuses on the Formlabs portion of the study, detailing design recommendations, injection conditions, and observed results.

Results

IPC demonstrated that a mold core printed in Formlabs Rigid 10K Resin, coupled with a soft PA12 frame, can produce thousands of polypropylene parts while reducing mold cost by 80–90% compared to traditional steel tooling.

Textures on final parts produced with the multi‑material mold illustrate the surface quality achievable when combining resin cores with a metal die.

Desktop 3D printing offers a rapid, low‑cost solution for fabricating injection molds. It requires minimal equipment, frees up CNC resources and skilled labor for higher‑value tasks, and integrates seamlessly into existing injection molding workflows.

Manufacturers can leverage in‑house 3D printing to create molds quickly and combine them with industrial injection molding to deliver a series of thermoplastic units within days.

Download the full report for a comprehensive summary of the technical study, including 3D‑printing guidelines and insights on mold assembly and process conditions.