Digital Manufacturing at Scale

It's not every day one sees 120 industrial SLA machines in one room. But that's what I got to see in a rather unassuming, even worn-down, building in Dongguan. This was truly digital manufacturing at scale.

360 Video (click on screen, pause, and pan around)

The Process

The main processes available are MJF (Multijet Fusion), SLA (Stereolithography), and metal 3D printing. By far, SLA accounts for the highest product volume here, and in industry, MJF has largely replaced SLS as the best quality for price considering both fixed and variable costs, like the price for powder quality.

There are basically two main parts to the digital manufacturing process: the 'digital manufacturing' and the post-processing. One is completely automated, and happens in vast, dim rooms with machines neatly lined up. The other is entirely by hand. This includes removing supports, sanding them smooth, and applying surface finishing to them.

Other than the standard support removal and surface finishing, shops like the one in the video usually offer spray painting (pictured in the video), electroplating, screen printing (for detailed patterns onto a flat face), and polishing.

For the metal 3D printed robots, they are sandblasted and heat treated. The support removal process is quite annoying, requiring quite a bit of dremel time.

The Result

There is a reason SLA and sometimes MJF are the go-to digital manufacturing methods in industry. Parts that come off these industrial machines, especially with the post-processing steps they do here, look much closer to injection molded parts. With very careful surface finishing and just the right paint mix, the part can even match anodized aluminum. Below are parts from metal 3D printing after polishing and from SLA printing after electroplating.