3D Printing Process Overview: SLA

What Is SLA? How Does It Work?

Stereolithography (SLA) is a 3D printing technology that uses photopolymerization to create models with high precision. This process involves an ultraviolet (UV) light curing liquid resin layer by layer, solidifying it into the desired shape. During the pre-build setup, structural supports are generated to stabilize the model during printing. Once the print is complete, these supports are manually removed, and the parts are washed in a solvent solution to eliminate any uncured resin. Finally, the parts undergo a post-curing process in a UV light oven to achieve full strength and stability.

SLA typically produces a smoother surface finish compared to other 3D printing processes, such as FDM. This is because SLA solidifies liquid resin using a laser, rather than melting and cooling a plastic filament. The result is parts with a smooth, almost glass-like finish.

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SLA

Stereolithography

Advantages Produces smooth, glass-like surfaces ideal for aesthetic prototypes. Complex part geometries can be achieved Excellent detail and high-resolution prints Suitable for both small and large parts due to high resolution and relatively large build envelopes.

Disadvantages Higher cost compared to processes like MJF, SLS, or FDM. High UV sensitivity that may lead to material degradation and fast aging Not suitable for moving assemblies Need of support structures for overhanging features Thin or detailed features may be fragile for end use applications Low production volumes, suitable mainly for prototyping and exhibition parts due to slower batch processing.