Summary I designed a smile ball that contains a small angry ball (hemisphere) inside. The ball consists of 5 main parts, and each of which is connected to the hinge-like joints. It is printed at once. So, it often remains stuck in printing. Be careful to get moving the joints. You need some elastic cords. They are used to open the big ball and come out the small angry ball. Print Settings Printer Brand: Printrbot Printer: Simple Black Rafts: No Supports: No Resolution: 0.2mm layer thickness Infill: 100% recommended Post-Printing How to assemble : https://www.youtube.com/watch?v=ZyEu_XU2HzU