Fused deposition modeling (FDM) and stereolithography (SLA) are widely used 3D printing methods due to their one-of-a-kind capabilities. Both are known for their versatility and ability to form complex shapes and overhangs with support structures during printing. Plus, they provide a speedier, more cost-effective way to build prototypes and some end-use parts. But how do you know which one to use? Use this guide to make an informed choice between FDM and SLA 3D printing.

About FDM 3D printing

Fused deposition modeling is usually the 3D printing technology that comes to mind when most people think about additive manufacturing. With more material options, it is widely used for low-volume production and quick prototyping projects. These include PC, ABS, and performance materials like nylon and Ultem. FDM has many applications, including functional bits, enclosures, and housings.

To build parts, FDM extrudes plastic filament within a nozzle, laying it down one layer at a time on the build chamber. This way, the printer can build parts with complex features. However, overhangs will require supports, which are removed during post-processing. Additionally, since FDM requires extruding thermoplastics through nozzles, there may be challenges in the resolution and tolerance. Sometimes, there are a few build blemishes or layer lines as materials heat and cool. However, even with aesthetic issues, parts built with FDM are great for functional testing.

About SLA 3D printing

SLA 3D printing builds parts one layer at a time using photocurable resins. While on the build platform, the resin is cured by a high-powered UV laser. Support structures hold the parts as they are built per layer, but these are removed post-process. However, stereolithography can build with accuracy to the CAD and ensures a good surface finish.

SLA is best for making aesthetic prototypes instead of functional parts. But for enhanced performance, consider materials that can replicate the mechanical properties of FDM filaments like nylon and ABS.

Not sure which 3D printer to use?

Consult our expert team here at HLH Proto for more details on FDM and SLA 3D printing. We can review your project at no cost to help you decide or recommend the best manufacturing method to eliminate the guesswork.