What is the Difference Between SLA and MSLA 3D Printing?

Within resin 3D printing there are a number of different manufacturing methods. Processes like SLA, DLP or MSLA are all available, differing depending on which light source or process by which the photopolymer solidifies is used. In addition, many large companies in the industry have also developed their own resin additive manufacturing solutions, with slight modifications that allow them to be patented as proprietary technologies. This is the case of BCN3D with its VLM 3D printing process, Prodways with MovingLight, or Carbon with DLS. However, today we want to focus on two specific methods which are SLA and MSLA. And though they may sound familiar, in fact that are extremely different. We took a closer look at how each one works, what their similarities are and, finally, how they differ from each other.

On one hand, stereolithography (SLA) technology uses a laser that solidifies the resin layer by layer in the 3D printer tank. Once the layer is finished, the build plate descends again to make way for the next one. Thus, the process is repeated until the final piece is obtained. On the other hand, the so-called Masked Stereolithography Apparatus (MSLA) is a modified form of SLA 3D printing. Although it is based on the same principle of light curing the resin using a light source, the method is somewhat different. Specifically, instead of using a laser beam to trace the layers, MSLA printers use a larger ultraviolet light source which is then selectively masked with an LCD screen to create the design.

The makeup of an MSLA 3D printer is different than its SLA counterpart

Characteristics of SLA and MSLA Technologies

As we can see, the main difference between SLA and MSLA 3D printing is the light curing process for the resin and the light source. Therefore, the composition and elements of the 3D printers will vary from one machine to another. As the exposure of the layer to UV light is different, it also affects the printing speed and production times. While traditional SLA 3D printers rely on the number of layers and the amount of material in each layer to be laser cured, MSLA technology relies solely on the number of layers being printed. This difference in operation means that MSLA solutions have a speed advantage on each layer, especially when printing multiple objects at once.