Spherical Die or Chaotic Cat Toy Ball

The STL file only contains one piece, which you need to print twice. The octahedral chamber inside has 6 vertices, and so causes the ball only to land on one of 6 “sides” when a weight/ball bearing is added inside! If you want, you can draw numbers on the outside with a pen and use it as a standard d6/cubic die. 

I unintentionally gave this to the cat one day, and he loved it! 

I used PLA. NO SUPPORTS NEEDED. Print at 100% density to make the most “fair” dice-- so that the density is [constant] throughout the solid parts. The cylindrical holes around the outside are indexing holes sized for very short pieces of 1.75mm filament. 

For a cat toy, it could be fun to scale up and maybe add multiple weights/bearings; just note that the indexing holes may not work exactly as expected any more.