The STL files are on thingiverse http://bit.ly/DSYoYo.
I modified some existing 3D models to suit my purpose and printed them out in silver PLA http://bit.ly/fil-ca on my #Printrbot simple metal.
Cut a section of chopstick and inserted in both halves of the yo-yo shells.
Waxed string with birthday candle and attached to yo-yo.
Spun it up and let it rip!
Project available on Tindie https://www.tindie.com/stores/SolidGround/
AWESOME!!!