Stereolithography is a 3D Printing technology that uses UV light and a liquid resin to generate high resolution physical objects.

In addition to a computer, there are three major components to SLA 3D printing. First, there is a tank filled with several gallons of photopolymer liquid, also called liquid plastic. This is where the printing occurs. Immersed in the tank is a perforated platform that moves up and down inside the tank as the printing process progresses. Finally, there is an ultraviolet laser responsible for hardening the photopolymer.

At the beginning of the process, a thin photopolymer layer is exposed above the perforated platform. The ultraviolet laser strikes the platform and traces the object’s pattern. Because the photopolymer is ultraviolet curable, it hardens when the laser hits it and forms the first layer of the object. After the first layer hardens, the computer lowers the platform, which reveals a new layer of liquid polymer. Once again the laser traces the object’s pattern, and the liquid polymer solidifies, binding to the already hardened polymer beneath it.

This process continues until the object is completed and totally submerged in the tank. Afterwards, the platform is raised and the object removed. Because of the toxic nature of the chemicals, the final printed product must be rinsed to remove the extra polymer. The object is then placed in an ultraviolet oven, where it is further cured. This final step is unique to SLA printing.

SLA 3D Printing in Practice

What is SLA 3D printing best known for? Generally, SLA has a faster print time than FDM and SLS, and it is often the most accurate printing method available due to the precision achievable with a laser. Though SLA requires that users “bake” their products to ensure they are properly cured, no physical modification is required because the end results have a smooth finish, unlike objects printed with FDM and SLS.

Despite the faster printing time and smoother finish, the market for SLA desktop printers is more limited than the FDM market. Formlabs’ printer Form 1+ is the best option for consumers interested in desktop SLA printing. They company provides a range of colored resin and a complete starter kit. Consumers should be ready to pay a bit more for an SLA printer, though. SLA is a more expensive method, and the photopolymer requires special handling. Furthermore, SLA printers don’t automatically factor in support structures where they’re required, so users must plan support into their design. SLA is best used for prototypes that need to be created quickly but won’t undergo harsh testing conditions.

SLA Printers here at 3D Supply Guys

Due to the limited market, we don’t yet offer SLA printers here at 3D Supply Guys. We do however offer a number of different printer brands featuring FDM technology. Our popular printer brands include Flashforge, Solidoodle, and 3Doodler. To see our full line of printers, please click here.