WARNING! This model requieres glue.
Print the center of the ball “Ball filament guides” in spiral mode (is uploaded already in the right position) and insert the filaments. I cut the filament at the top, retract a little bit and cut flush the bottom. If you do that you can then push the bottom slightly up again and there won't be filament ends outside of the holes.
Push “core top” through “ball detail” and apply glue in “core top” hole. It is gonna end up hidden so don't worry if you are messy. Push “core bottom” through the other “ball detail” and encapsulate “ball filament guides” between them.
Apply glue to down and top cover and glue them in place. Finally, glue the hanger and enjoy.