These gears are half of the entire perpetual motion machine. The machine itself is described in the youtube video here: https://www.youtube.com/watch?v=jgAnponHWgU The whole concept is that I was trying to make a perpetually off-balance machine by making the movement of the weight occur in an entirely seperate plane than the rotating wheels. Since everything rotates at 1:1, I thought that it would maintain balance except for the weight. In addition to the STL files, you will need to print out three of the following gears at 2x the scale: http://www.thingiverse.com/thing:149544/#files As you can see in the video, I had to modify one of the gears (cut out the center and drill holes in it) to mount it to the frame. Bearings help keep it running smooth. The frame could be made out of anything. I used plastic that I cut with my router, but wood may be much easier to use. Threaded rod from the hardware store is used as the shaft of the axles. Aluminum tubes on the threaded rod keep the gears in the center of the threaded rods. Make sure the large gear in the very center does not move. The complicated part is getting the 3mm shaft inside the bearings and in place. The weight (bolt and nut) rotate on that shaft. I hope that posting the STL files that I have made, somebody may improve on them or the design in general. Have fun!