Comparing 3D Printing Technologies: FDM vs SLA

Two different approaches

FDM (Fused Deposition Modeling) builds parts by depositing melted thermoplastic filament layer by layer through a nozzle. SLA (Stereolithography) cures liquid resin layer by layer with light. One melts a solid plastic, the other solidifies a liquid; this difference affects everything from the part's appearance to its strength.

Surface quality and detail

Layer lines are almost invisible on SLA parts and fine details come out sharp. That is why SLA stands out for jewelry and casting patterns, dental models and presentation prototypes. Layer lines are more visible with FDM; however, with the right layer height and orientation they are rarely a problem for functional parts.

Strength and materials

FDM offers a very wide range of materials, from PLA and PETG to engineering materials such as ABS, ASA, PC and carbon fiber reinforced nylon (PA-CF). With carbon and glass fiber reinforced filaments, rigid, lightweight parts are possible. Standard SLA resins are more brittle; FDM is usually preferred for load-bearing parts.

Size and cost

Large parts can be printed economically with FDM; on our high-capacity industrial FDM machines we can produce large parts in one go. SLA build volumes are smaller and the cost per part is usually higher.

In short, which one?

• Functional prototypes, brackets, enclosures, large parts: FDM
• Fine detail, smooth surfaces, casting patterns: SLA
• Multicolor parts without painting: multicolor FDM (8 colors)

If you are not sure, send us your file and our engineers will recommend the best technology for your part.