Stereolithography (SLA) is an industrial 3D printing process used to create concept models, cosmetic prototypes, and complex parts with intricate geometries in as fast as 1 day. A wide selection of materials, extremely high feature resolutions, and quality surface finishes are possible with SLA. SLA is a go-to choice for 3D printed models that require accurate features and a smooth surface finish.
A photosensitive suspension (photopolymer resin) is exposed by light (of certain wavelength) so it cures. The exposure pattern for each 3D slice is defined by a 2D photo mask (ultraviolet (UV) laser, UV light projector/DLP or LCD). After a layer is photocured, the Z axis moves up for the next layer of the 3D object. An FEP film clamped against the glass is used as the release layer.
There exist three common photo mask and light source combinations:
-ultraviolet (UV) laser
-Digital light processing (DLP) projector and UV lamp
-LCD panel and UV lamp
The type of photopolymer resin used (visible-light-curing or ultraviolet (UV)-curing) has to match the type of photo mask and light source combination.
-resin: UV-curing resin with absorption range 250 to 450 nm
-light source: UV lamp/LED 405 nm
-photo mask: LCD panel allowing to pass the UV lamp frequency
SLA 3D prints are often used for final fit checks before moving to injection molding services. Stereolithography is an additive manufacturing process that can 3D print parts with small features, tight tolerance requirements, and smooth surface finishes.
|Maximum build size||1700 x 800 x 600 mm|
|Minimum feature size||0.05 mm|
|Minimum layer thickness||0.02 mm|
|Typical surface finish||3 – 10 microns RA|
The table below depicts the general tolerances for industrial-grade stereolithography (SLA) services. Stresses during the build, support strategy and other geometry considerations may cause deviation in tolerances and flatness. Improved tolerances may be possible with a manual quote review, after successful completion of a prototype build, and must be approved on a case-by-case basis.