Wrong Way Nut (Mk2)

Two nuts travel opposite directions on the same thread! As seen on YouTube! http://www.youtube.com/watch?v=o-fPsvqjqZI

Update 27 Oct 2011: I've uploaded a new trick nut triplescrew_backward_floor.stl which eliminates superfluous slack and reduces the overhangs to where they might be buildable on a Makerbot.

The YouTube video inspired Thingiverse user msruggles to design his own "Screwy Screw" thing. The STL files below are the originals, which were used to make the video, which inspired msruggles to make Screwy Screw, which inspired me to upload the STL files below...oh gosh, I'm completely lost!

Don't know how it works? Obviously there's a trick to it, but I encourage you to try to figure it out before you "spoil" the fun by downloading the files. Try designing your own!

More discussion on my blog at http://mysd300.blogspot.com/search/label/screw