This design is a quick test of a single-row omniwheel that attempts to maximize the number of rollers (for smoother rolling) while also maximizing the roller diameter (for easier transverse motions). It has an roller diameter to O.D. ratio of 4:1, and uses 26 rollers that leaves less than a 14 degree gap between rollers. Overall, it has a 3" diameter and a hub with a 5mm bore.
All 26 rollers snap into place without the need for any separate axles.
Print 1 hub and 26 wheels. All of the wheels snap into place pretty easily, except for the last one which which takes a little bit of work.