I originally designed this as a mini ornament. It looks great at that size (1X), but looks even better at 1.5X and 2X. At 1X, it's about the size of a golf ball. At 1.5X, it's a standard Christmas ball size. At 2X, it's about the size of a grapefruit. It will scale up even more if you want to. I assume most people will print this at 1.5X, so that's what I've used the the time estimate.
Not for commercial use. Please see license agreement.
The cover photo shows it at 2X.
I've provided a couple versions of the ball - in 2 pieces and in 1 piece (not including the cap). I recommend printing it as 2 pieces. It's a lot smoother that way and the ball prints without supports. I've provided my PrusaSlicer 3MF files and MK3S+ GCODE for the 2 piece print at all 3 sizes. I've provided the ball as 1 piece mostly in case someone wants to experiment with cutting it in a different place or you want to print the ball as 1 piece using a 3 color filament.
You might think this needs infill everywhere, but it really doesn't. I used height range modifiers in PrusaSlicer to add a few layers of infill (25 - 30%) in 5 places where something starts to print unsupported. It printed really well and it's light. Printing the 1.5X ball with 25% infill everywhere increases the final weight by 50% and adds 2.5 hours to the print time.
I printed most of the ornament with just 1 perimeter. At the bottom of each half, where the halves later get glued together, I used 2 perimeters. I used 2 and the top of the top half and 3 at the top of the bottom half. The cap is printed with 2 perimeters everywhere.
I printed the 1.5X and 2X balls with supports to get a cleaner print on the dome, but that part of the print is just about impossible to see when the ornament is glued together. I'm just a perfectionist.
I used custom seams to put as many as I could on the inside of the ball where they don't show.
I printed the 1X ball with 0.1mm layer height and the other sizes at 0.15mm.