This is a new 3D printed rotor prototype i designed, with a snap-hook shaft and press-fit circular magnets! 

I managed to use 4 circular magnets with the new rotor that makes the magnetic field more uniform across its whole area.

The metallic shaft was also eliminated. Instead it was made part of the 3D rotor model, At the end of this shaft are two snap-hooks that lock the rotor inside the bearing. 

This feature makes this brushless motor more cheaper and easier to assemble. Its now just a three step process!

• Put the magnets in the rotor
• Put the bearing in the pcb
• Snap in the rotor onto the pcb