Stereolithography (SLA)

Stereolithography (SLA) models offer the most accurate type of fit/form prototype for the verification of any design before committing to your chosen production route. Its high accuracy and good surface finish makes it the preferred choice for designer models, engineering verification and master patterns for silicone rubber molds.

3D Printers

3D Systems | Stereolithography (SLA)


FormLabs | Stereolithography (SLA)


FormLabs Form 2


3D Systems Materials

  • Rigid, PC-Like
  • Semi-flexible
  • PP-Like (Accura 25 / VisiJet SL Flex)
  • High-Temp ABS-Like
  • Technician’s Choice
  • High-Impact ABS-Like
  • High Temp PC-Like, Rigid
  • Durable
  • High Resolution
  • ABS-like, Gray
  • ABS-like, Black
  • ABS-Like

FormLabs Materials

Flexible Resin Cartridge (FLGR02)Clear Resin Cartridge (GPCL02)Dental SG Resin Cartridge (DGOR01)Black Resin Cartridge (GPBK02)White Resin Cartridge (GPWH02)Grey Resin Cartridge (GPGR02)Tough Resin Cartridge (TOTL02)Castable Resin Cartridge (CABL02)

  • Flexible Resin Cartridge (FLGR02)
  • Clear Resin Cartridge (GPCL02)
  • Dental SG Resin Cartridge (DGOR01)
  • Black Resin Cartridge (GPBK02)
  • White Resin Cartridge (GPWH02)
  • Grey Resin Cartridge (GPGR02)
  • Tough Resin Cartridge (TOTL02)
  • Castable Resin Cartridge (CABL02)
What is Stereolithography?

What is Stereolithography?

SLA® Production Printers build accurate parts directly from 3D CAD data without tooling by converting liquid materials and composites into solid cross-sections, layer by layer, using an ultraviolet laser. The bed then lowers, the part is coated with a new layer of resin, and the next layer is built on top of the others until the part is finished. When a part is complete, it is cleaned in a solvent solution to remove wet resin remaining on the part surface. Afterward, the part is put in a UV oven to complete the curing process. SLA® Production Printers offer high throughput, build size up to 1524 mm, unmatched part resolution and accuracy, and a wide range of print materials.  No process addresses a wider range of applications, including the most demanding rapid manufacturing applications.

When Charles ‘Chuck’ Hull, the founder of 3D Systems, invented Stereolithography, SLA, in 1986, he launched a revolution in product development across every marketplace from transportation, recreation and healthcare to consumer goods and education. Through continued innovation we extend our technology leadership, offering customers new and improved Production Printers and Print Materials and expanding our patent portfolio.

(View the video to the left to see how SLA 3D printing works.)

SLA is all about precision and accuracy, so it is often used where form, fit and assembly are critical. The tolerances on an SLA part are typically less than .05mm, and it offers the smoothest surface finish of any additive manufacturing process. Considering the level of quality SLA can achieve, it’s particularly useful for creating highly precise casting patterns (e.g., for injection molding, casting and vacuum casting) as well as functional prototypes, presentation models, and for performing form and fit testing. SLA technology is extremely versatile and it can be used in any number of areas that require precision above all else.

Keep in mind that, unlike with SLS, SLA parts do utilize support structures, and they require a bit more post-processing. But the post-processing options are also some of SLAs greatest advantages. Models can be vapor honed, or bead or sand blasted. SLA parts can even be electroplated with metal, such as nickel. Electroplating not only makes the part significantly stronger, but it also makes the part electrically conductive and more dimensionally stable in moist environments.

In terms of benefits, SLA allows us to save time on highly precise parts, especially when you require a number of functional prototypes or a quick single casting pattern. SLA brings us painstaking accuracy without the painstaking time. Because of SLA’s speed and precision, prototypes are easy to make and faithful to the final design, which means we can identify design flaws, collisions and potential mass-manufacturing hurdles before production begins. For low- to mid-volume parts normally machined from polypropylene or ABS, SLA provides comparable characteristics and doesn’t require slow, expensive retooling for customization or in the event a tooling change is required. In addition, SLA allows for lower material costs, as the unused resin stays in the vat for future projects.

SLA materials are wide ranging in mechanical properties and offer wide application opportunities for parts requiring ABS or polypropylene-like characteristics such as snap-fit assemblies, automotive styling components and master patterns. SLA materials are available for higher-temperature applications and clear materials are available with polycarbonate-like properties. Biocompatible materials are available for a wide range of medical applications such as surgical tools, dental appliances and hearing aids. Other materials are specifically formulated for patterns, offering low ash creation and high accuracy while also being expendable.

Anatomy of the SLA Process

Anatomy of the SLA Process

Stereolithography (SLA) is often considered the pioneer of the additive manufacturing processes,  with the first production systems introduced in 1988 and patented by 3D systems founder Charles (Chuck) W. Hull. The SLA process utilizes a vat of liquid photopolymer resin cured by ultraviolet laser to solidify the pattern layer by layer to create or “print” a solid 3D model.

The SLA process utilizes a vat of liquid photopolymer resin cured by ultraviolet laser to solidify the pattern layer by layer to create or “print” a solid 3D model.

An Ultra Violet (UV) laser beam is directed by a computer guided mirror onto the surface of the UV photopolymer resin. The model is built one layer at a time from supplied 3D CAD data.

The laser beam traces the boundaries and fills in a two-dimensional cross section of the model, solidifying the resin wherever it touches. Each successive layer is applied by submersion of the build platform into the resin as the part gradually develops and the platform descends into the liquid resin.

Once the model is complete, the platform rises out of the vat and the excess resin is drained. The model is then removed from the platform, washed of excess resin, and then placed in a UV oven for a final curing. After curing SLA parts are then ready for post processing as required by the specific application.

  • Nickel Plated
  • Painted
  • Primed
  • WaterClear

Frequently, parts produced by SLA are used as master patterns (pattern transfer process). The pattern is transferred to urethane castings using silicone rubber molds (SRM) or utilized for metal investment casting.

Rapid Prototypes:
•  Design Appearance Models
•  Proof of Concept Prototypes
•  Design Evaluation Models (Form & Fit)
•  Engineering Proving Models (Design Verification)
•  Wind-Tunnel Test Models

Tooling and Patterns:
•  Investment Casting Patterns
•  Jigs and Fixtures


•  Smooth surface finish
•  High precision
•  Short lead times
•  Wide variety of material and post processing options

Case Studies

3D Systems Case Studies | Steriolithography

You’ve seen it: The bobblehead that could only be identified as the star athlete by the name or number on his or her uniform. Or the doll that fails to capture an actress’ fine…

By Kendall Joudrie, Thinking Robot Studios. (Story Excerpt)

In February 2014, the team at American Precision Prototyping (APP) was presented with a unique challenge: redesign, prototype, cast, decorate and ship 150 cast ure

There’s a moment that every industrial designer dreads: When his or her ideal design bumps up against manufacturing reality. Confederate Motors has faced that moment many times in…

Dometic Sanitation Corporation designs and manufactures onboard sanitation systems and related equipment that exceed boat builder and end user expectations while protecting the…

The SEMA show is considered the biggest annual trade event in the US for after-market automotive parts manufacturers, delivering a lot of excitement, and offering opportunities…

Eye-Com Corporation is dedicated to the development of eye tracking technology to improve and save lives, support the advancement of research, and revolutionize human-technology…

In 2013 Apple sold more than 170 million iPads® worldwide. With a reported 500 million iPhones® in use along with millions of Samsung® Galaxy phones and a variety of other mobile…

Generac is a manufacturer of standby and prime power generator sets for industrial, telecommunication, commercial, small business, mobile and residential applications.

Gyrus ACMI leads the world in developing ‘See’ and ‘Treat’ procedure solutions for less invasive surgeries. Gyrus ACMI provides physicians with the power to treat with PK…

Redfish Instruments develops electronic devices that function in tandem with the Apple iPhone, iPad, and iPod-touch.  Redfish Instruments’ iDVM device is the world’s first iPhone…

Loftgoods, a leading player in the home furnishings business, had an issue. They had a wonderful idea, a fantastic new concept and a very short time frame to get a new product to…

Formula 1 is a sport revolving around engineering innovation where teams work relentlessly to reach and maintain a competitive advantage. The research and development machine…

There’s nothing like seeing a scaled-model of a development project to help sell the architectural vision. That belief drove Phil Whitelaw to create, a successful…

Annoyed by the inconvenience of the standard adhesive/Velcro-based method of attachment for his Florida E-Pass, Brian Gulliver decided to do something about it by designing an…
When the maker of James Boag’s Premium Lager was faced with the prospect of a potentially costly overhaul of its tooling systems, glass bottle supplier Orora knew it had to find…
The very first customer job that Todd Reese, president of Noblesville, Indiana-based rapid prototyping service provider Realize Inc., fed his ProJet® 7000 stereolithography (SLA)…

Accura® Xtreme and Quickparts- Born to Ride Mobility goes ‘e’. This is a trend that Craig Bramscher foresaw as he founded the e-motorbike think-tank Brammo, Inc. in Oregon a few…

SuppServe is a boutique package design firm located in northern California that specializes in single-serve dispensing solutions.  “Inventors, innovators, marketers and sellers of…