Stereolithography

Stereolithography is a digital fabrication method where a digital 3D model (CAD) is divided into layers, then created in real-life through the printing process, until a solid 3D object is made.

SL creates a shape from a liquid resin, usually in a vat, where each layer is created when exposed to light.

Once hardened, each layer moves out of the way to make room for the next layer in the build. The light source can be a laser or a high-precision DLP projector, which will expose specific areas of each layer until hardened, and this process is repeated over and over. Once completed, the object is removed from the vat, finished to remove rough edges and any structural supports, then cleaned in a rinse. It may also be cured an additional time for durability in a special oven or light box.

The benefit of SL is that it can create very intricate designs because of the high resolution of the light-induced process. SL works well for a wide variety of applications in jewelry, prototyping, dental, medical devices fabrication, tooling, etc. The resins used in SL can be mixed with additives, such as metal or ceramics, to create a wide variety of product finishes, appearances, and strengths.

The photopolymers used to create projects are photoreactive, and care must be taken to store and handle these materials. While hobbyists aren’t as likely to use SL for their first printer, the manufacturing and professional design opportunities with SL are making it a popular choice in many industries, with a wide option of vat sizes and lights being sold to create just the right end- product for engineers.