Mecanum Wheels

This is a mecanum wheel based off of Zaggo's design. I beefed up the area around the bearings and made the rollers a little wider. I found that without the thicker area around the bearings, the plastic cracks and breaks off. I have uploaded two versions. One accepts an 8mm shaft and the other accepts the standard 5mm stepper motor shaft.
A short video of their operation:
https://www.youtube.com/watch?v=NohwUDOjMZY