3D Inserts: the research that separates the wheat from the chaff

Published on May 19, 2026 | Translated from Spanish

A study from the University of Navarre has analyzed the performance of inserts manufactured using additive techniques for injection molds. The research reveals that success depends on the process, material, geometry, and molding parameters. The results show notable differences between technologies, from 85 cycles for photopolymerization to over 500 cycles for laser sintering in metal powder.

Photorealistic engineering visualization of injection mold testing laboratory, metal 3D printed inserts with visible layer lines being inspected under microscope, comparison station showing damaged photopolymer insert after 85 cycles next to intact sintered laser metal insert after 500 cycles, injection molding machine in background ejecting a plastic part, white light interferometry scanning surface roughness of inserts, digital caliper measuring insert geometry, dramatic industrial lighting casting shadows, ultra-detailed metallic textures, polished steel mold base, technical scientific atmosphere, cinematic depth of field

Metal vs. Polymer: Durability and Thermal Dissipation 🔥

Inserts made by laser powder bed fusion exceeded 500 injection cycles, showing resistance and adequate heat dissipation capacity for series production. In contrast, those made by material jetting achieved 116 cycles, and photopolymerization ones, 85. However, surface roughness remains a common weak point, requiring post-processing. Material extrusion is relegated due to its surface finish and risk of delamination.

Roughness: That Little Big Problem Nobody Wants to Polish 😅

Because yes, you can have a metal insert that withstands 500 cycles like a champ, but its surface looks like sandpaper. The good news is that post-processing exists; the bad news is that nobody includes it in the initial budget. And material extrusion, poor thing, comes with delamination and a finish like expired yogurt. In the end, technology advances, but manual polishing remains the unsung hero of the story.