I was doing these quietly for a year or two and stopped after getting huge orders from china twice, thought it would be bootlegged but the print quality isn't so good yet and most of the parts have "traps" designed via undercuts, etc... that would not be possible to create with traditional manufacturing.
You can see the full set by googling "blackographic flickr". again, stopped doing these but can answer 3D print questions. For the design itself I've been using Rhino a 3D modelling program that I self-learned 5 years ago. Pretty hard as a starter program to get into.
https://imgur.com/a/FT0h87J