Stereolithography (SLA)

What is Stereolithography?

Stereolithography is a form of 3D printing which involves a UV-sensitive resin that cures as a UV laser scans over it, drawing 2D patterns layer-by-layer, building the resin into a 3D model.  It was the first patented method of 3D printing and has only recently gained traction in the consumer market primarily due to more cost-effective scanning lasers and the popular Formlabs printers.

Why would I use this process to create a 3D part?

In general, SLA printing offers high-fidelity parts for cheaper than more commercial processes like PolyJet printing. SLA offers a decent option for purely aesthetic parts and even functional parts that require precision or isotropy (as opposed to anisotropy found in processes like FDM).

Benefits of SLA over other processes:

  • High-fidelity (~ .01mm accuracy in X and Y directions for most cases)

  • Smooth surfaces (down to 0.025mm layer height)

  • Lower cost than industrial processes like PolyJet

  • Large variety of resin materials  (see what we offer at

  • Isotropic material properties once cured

Drawbacks of SLA over other processes:

  • Higher cost than FDM

  • Additional cure time required for many resins

  • Models are printed solid (no "infill" like FDM processes) 

  • No commercial options for multi-material in a single print

  • Must use tree-supports which can leave ‘nubs’ of residual material (this can typically be removed in post-processing)

  • UV curing required for post processing (more post processing time than FDM processes)

  • Usually smaller build volume than most other processes