I started with freecad to design my 3d prints, and am now learning the path took for CNC code generating. Pretty food software, but the learning curve is a bit steep. At least there are many youtube channels dedicated to it. Blender can also be used to generate printable 3d models.
https://www.schlockmercenary.com/ webcomics has a very interesting story arc about teleporters and why they were replaced.