Most 3D printers don’t take up a lot of space, but they can be pretty bulky and awkward to travel with. [Jón Schone] needed a compact folding 3D printer for a secret project on his YouTube ...

[Luke Towan] has a cool HO scale Escalator mostly made of 3D printed parts ... magical about the stairs unfolding at the bottom and folding up at the top. But they’re very hard to model.