Printed with a 0.4mm nozzle, 0.2mm layer, PLA, 2 walls, 15% infill, precise perimeters, no supports. Thanks for the useful advice in the comments: In the slicer settings, you must change the seam position to random, then the parts do not weld, do not stick together, and move very well. The gaps are chosen very well by the author: everything works without changing the sizes and settings. The child is very happy with this toy. Thank you very much for a very good model.