Model originally uploaded to Thingiverse at https://www.thingiverse.com/thing:3239327.

i came up with this hub design for easy assembly. you inset hex rod into ball, then, insert ball into hub. it pops right in. after inserted to hub, the ball can rotate.

you can place up to 6 ball/rods into the hub. connecting several of these can give a geodesic dome or sphere. either truncated (with 3 ball/rods ) or full geodesic (with 6 ball/rod and 5 ball/rod combos)

i added a step file so you can modify as you please.

no supports needed. hub has flat spot to hold to table well enough.