by alan_one, published
A simple yo-yo.
Update! Here's my improved yo-yo design, with accomodation for screws to hold the pieces together: http://www.thingiverse.com/thing:110964
Assemble either traditional or butterfly style by pressing the pieces onto a length of 1/4" diameter wooden dowel - wood is really the best material for a fixed axle and will allow the yo-yo to sleep easily. The dowel should be about 1 3/8" long. Happy yo-ing!