Two researchers from the Zurich University of Applied Sciences (ZHAW) have developed a 3D printing process that overhangs of 90 ° without Support material allows. The technology called “RotBot” works by means of an additional axis for the print head and also requires a new calculation of the print data. Existing printers could be upgraded with it.

Print with kink While conventional 3D printers only run parallel to the printing plate, with this printing method the nozzle is moved around 45 ° inclined and moved on an additional axis of rotation. Due to the tilted head, the pressure of support material is not necessary. This saves time, material and there is no need to remove the support structures, which means that there are no visible traces on the surface.

The nozzle is tilted. This allows additional 45 ° overhang to be achieved.

(Image: ZHAW School of Engineering)

The ZHAW researchers have also redeveloped the print file calculation so that 3D printers get the right print data at all: For the new process, the 3D object is divided into cones instead of layers. To do this, they have written two new algorithms that prepare and post-process the data for slicer programs. So you can still use the usual slicer, which converts a 3D model into instructions for the 3D printer.

Modify instead of new buy This technology could be used to upgrade existing 3D printers, according to the researchers. New printer purchases are then not necessary. They hope that a RotBot upgrade kit will be released soon.

Four years ago, two students at the university had developed a 3D printer with a movable printing table that can also print large overhangs. It had six axes to move both the print head and the printing table. At that time, however, control using software was still a problem. (stri)