Stereolithography: the 3D-printing process

Stereolithography 3D printing

The 3Dvarius is 3D-printed by stereolithography, one of the oldest technology used in 3D printing processes. It has been introduced by Charles Hull, in the United States, at the beginning of the 1980s. The very first machine was officially commercialized in 1988 by 3D Systems.

The stereolithography (or SLA) uses photopolymerization to create models from a digital 3D file designed with one of the many software on the market (Maya, Catia, 3DSMax, etc.). Before going on with the print job, another software will perform a file analysis so to precisely determine which printing operational mode is to use in the model fabrication.

Nowadays, dozens of SLA printers are available on the market. They are of good quality and have variable prices; indeed, the quality goes together with the price…Therefore, you can find entry level SLA printers at €4000, but professional printers can reach much higher prices. A high-precision professional printer can cost between €500 000 and €1 000 000! The 3Dvarius is printed on that type of SLA 3D printer.

How works stereolithoraphy?

Stereolithography printer is made up of:

  • A basin to be filled with special 3D printing resin
  • A mobile platform to progress within the resin
  • A scraper system
  • And a UV laser.
Stereolithography SLA

Image from univ-reims.fr

In stereolithography, the part is printed on the platform, then plunged into a special 3D-printing resin. The photopolymerization process of the resin is realized by the UV laser.

The 3D-printing follows a cycle that can be broken down in several steps. First of all, the laser sprays liquid resin onto the surface, according to the digital 3D model provided to the printer, which prints it layer by layer. Then, the scraper passes so to get rid of the excess of resin. And finally, the mobile platform goes down so the laser cures a new layer. Therefore, there are as many cycles as necessary layers to get to the final item. The number of layers and cycles will define the printing time.

Here below, the 3Dvarius printing process using stereolithography.
3D-printing 3Dvarius

The printing concludes with several post-treatments, including putting the part into the oven in order to finalize the polymerization and improve the material resistance. Once the object is printed, it is also necessary to clean it up with specific cleaning solutions and give it the desired shape. In the case of the 3Dvarius, many others post-treatments and adjustments are required to obtain the final version of the electric violin. Feel free to have a look at the 3Dvarius printing process in the below video.

References: Wikipedia, 3Dvarius, 3DNatives.