Just threw these together, but I could get the outer wall from the cone to the ball stem to join easily, so it's open there. I did a meshmix of it to close it up, but it also got rid of some thread detail and it didn't want to screw on too tightly.
coke-2-liter-cap-with-ball-2.skp | 3.4MB | |
coke-2-liter-cap-with-ball-2.stl | 410.2KB |