A Guide to Post-Curing Stereolithography (SLA) 3D Prints

Each Formlabs Resin is formulated with advanced, light-sensitive polymer chemistries. Formlabs stereolithography (SLA) 3D printers, such as the Form 3+, Form 3B+, Form 3L, and Form 3BL use 405 nm lasers to cure the liquid resin, producing a highly accurate solid part.

When an SLA part finishes printing, it remains on the build platform in a “green state.” This means that while parts have reached their final form, polymerization is not yet fully completed and the part has yet to attain maximum mechanical properties. Post-curing with light and heat is key to unlocking this last mile of material properties for SLA 3D prints. For biocompatible materials, postcuring is necessary to achieve the safety standards determined by regulatory agencies.

Achieving optimal properties is especially essential when using functional or specialty resins. Form Cure and Form Cure L, the two post-curing solutions from Formlabs, are designed to postcure parts printed in Formlabs Resins with speed and consistency. Our engineers developed Form Cure and Form Cure L specifically to work with Formlabs Resins, using the same 405 nm light as the lasers in Formlabs SLA 3D printers. Parts are heated and automatically rotated in the reflective chamber to ensure an even and consistent post-cure.

This guide will help you understand how post-curing affects the key properties of Formlabs materials. We’ll cover post-curing recommendations for material-specific applications, as well as strategies for avoiding common issues.

Any resin used in SLA 3D printing can be thought of as a highly cross-linked macromolecule, or a continuous network of polymer chains (monomers and oligomers).