These auxetic structures swivel and expand in surprising ways! This is a 5x5 variation with a total of 25 squares, each 18x18mm. A cool demonstration of auxetics that is fun to fidget with.
Printing Guidelines
Fairly loose requirements, just make sure your printer isn't overextruding and has decent cooling so none of the parts fuse. I used 0.16mm layer height, 3 shells. No supports!