A free software license that requires that all work based on this must also be free software as in freely remixable and sharable by anyone under the same license but may be used commercially.
Light-weight print bed gimmick for core-xy 3D-printers: Not eccentric nuts but elastic deformation fit wheels to an aluminium 2040V profile as a z-axis.
A T8 2 mm pitch 8 mm lead nut is also 3D-printed.
Vaseline may be a good lubricant between the lead screw and PLA nut.
Materials and methods
Layer Height: 0.2 mm
Wall Thickness: 1.76 mm
Top/Bottom Thickness: 1.2 mm
Infill Density: 20%