Beaver tail indexing mechanism

Made in Diamond Age PLA on an Ultimaker 1. Designed in MOI.

I designed this about 3 months ago and am no longer sure where I got the idea from, though it may well have been from here: http://www.mekanizmalar.com/beaver_tail.html

Here's a video - partially obscured by my hand, I'm afraid: http://youtu.be/Fe-RzC_8ijk