What Is Stereolithography

Stereolithography refers to the process of taking 3D product designs and building them layer by layer in a vat of UV curable resin. Founder of 3D Systems, Chuck Hall first coined the term Stereolithography in 1986.

The Process

The Stereolithography process follows the following steps:

  1. Using proprietary software a 3D computer generated file of the prototype model is sliced into a series of fine layers. Support structures are also added automatically during this stage.
  2. Once converted to STL format the 3D file is then set to print on the Stereolithography machine.
  3. Using a UV laser beam the Stereolithography machine traces out the first cross section onto a VAT of UV curable liquid resin. On exposure to the laser the liquid resin cures.
  4. Once this first layer is complete the platform drops down by (0.05-0.15mm) applying a fresh layer of resin to the surface. The laser traces out the next layer curing the resin and bonding it to the layer below.
  5. Layer by layer the process is repeated until the prototype model is “grown” in the resin.
  6. Once the object has finised building the machine platform rises allowing any excess resin to drain away.
  7. The prototype model is then removed from the platform, where SLA technicians wash the model and remove any support structures.Once the model has been cleaned it can be finished and painted by hand to meet individual project requirements.

The Benefits of Using Stereolithography

  • Time Savings- Prototype models can be produced within days following receipt of final 3d CAD data eliminating the delays associated with tooling and more traditional model making methods.
  • Cost Savings - Identifing product design issues during the tooling process can prove costly, the use of SLA models allows for early design verification thus minimising the risk of such errors.
  • Tight Tolerences- Thanks to high resolution SLA machines it is now possible to achieve tight tolerences of as little as +/- 0.005″ can be achieved. The SLA process can make extremely accurate and highly complex components with ease.
  • Tough, Functional Prototypes- Developments in the range of materials available for the Stereolithography process have resulted in tougher more functional parts. Prototype models produced using the SLA process are now testing tolerent.
  • Design to Market faster- In addition to speeding up the design process, Stereolithography requires a limited number of secondary operational steps thanks to the high quality surface finish produced. This allows low volume production pieces reach the market before the competition.

Since its introduction over 20 years ago the Stereolithography process has undergone significant transformation moving this Rapid Prototyping technology closer to the realms of Rapid Manufacturing. As even tougher materials emergeit is likely that even more firms will turn to Sterolithography to meet their low volume production needs.


Post time: 02-11-2017