This fun print was made mostly to try out dual-color filament (not required), but it also works as a useful pen holder. The spherical holder is simply held in the base by it's own weight. The spherical holder and the base are effectively a ball joint, so the sphere is free to rotate in all directions. 

Changes in this variant from the earlier model (see remix) :

• Some additions to emphasize the dual-color effect (these also somewhat reduce the amount of possible rotation)
• Larger size

While the use of dual color filament is not a requirement, it does make for a very nice effect.

Notes : 

• The hole for the pen is 12mm ID (I assume it could be scaled up for larger pens).
• The print requires the use of “fill” to add weight. I used steel shot for shot-blasting, but sand would also likely work.

Print And Assembly Instructions

For my print I used MatterHackers Quantum dual-color PLA for the sphere and the base. I printed the Plug for the fill hole in the Base with “normal” PLA. In general :

• 0% infill
• 3 perimeters

For the dual-color filament, I changed the print temperatures as follows :

• First layer = 220°C
• Other layers = 225°C

FILL : 

Note that the sphere part must include a pause about at about 70% of the sphere height to allow the sphere “fill” to be added (see photos). Be careful not to fill the partially completed shell completely or you will risk interfering with the print head when the print resumes (ask me how I know!).

The Base has a fill hole and screw Plug. Fill the Base from the bottom via the fill hole, and screw in the plug to seal in the fill.
 

CAD

The OnShape 3D CAD files for this are here :

https://cad.onshape.com/documents/31fef93c7901f99c4fc2c600/w/35d9363379a1ad363b556d46/e/b65618c19b67641a62838b9c