Ten years ago, the concept of having an affordable 3D printer on our desks producing high-quality, repeatable prints, with sub-mm accuracy, in a wide range of colors and material properties, was just that. a dream. But now it’s reality. The machines that are now so ubiquitous to us hackers largely operate on the FDM principle of shooting molten plastic from a moving nozzle, but those aren’t the only games in town. A technique that has also been around for donkey years is SLS or Selective Laser Sintering, but machines of this type are big, heavy and expensive. However, having one in your own shop now feels a little less like a dream and more like a reality, with the SLS4All project from [Tomas Starek] on hackaday.io.
[Tomas] has been busy over the past year working on the design of its machine and is now almost done building and testing the hardware side. SLS printing works by using a roller to transfer a layer of powdered material onto the printing surface, then directing a medium power laser beam onto the surface to heat and bind the powder grains into a solid mass. . Then the bed is lowered a bit and the process repeats. Heating the bed, powder, and surrounding air is essential, as is humidity control, and it’s also a little tricky to maintain the shape of the laser beam across the entire surface of the bed. They are all obstacles [Tomas] must overcome, but the test machine is complete and is in a good position to begin this process control optimization fun.
Hardware-wise, the frame is the usual aluminum extrusion and 3D-printed case, with solid aluminum plates wherever needed. The electronics are based on a Raspberry Pi (running Klipper) with a BigTreeTech 1.4 turbo motherboard handling the interfacing. The 5W blue laser is aimed at the surface of the powder using a pair of galvanometers, which looks easier to get than it will be – we expect there to be quite a bit of “pleasure” in controlling the size and shape of the spot and ensuring it remains consistent across the entire surface of the build surface. Really fun times, and I’m crossing my fingers for that [Tomas] go over the details and get some good impressions soon!
Those who have been here a while may recall that we covered the OpenSLS project a while back, and while we’re talking about 3D printing as an alternative to FDM, here’s a little something about the printing with metal, as long as you are very patient!