3d printed extruder for continuous clay shapes

Scot A. Brown published a post on 3d printed rotational extruder "Rotruder" that produces continuous stream of clay objects. The rotating parts of the extruder form a mold when they are closing together.
Interesting concept and example of mold+extruder being made by with 3d printed parts. I think it could be used with other pasty materials or even food.
I have not found any design or technical documentation.It would be interesting to see the mechanism of power transmission that turns the six mold wheels.

Source:

http://www.scottabrownceramics.com/post/112148811594/3d-printed-extruder-increasing-the-dynamic-of

here are some files to make it on GrabCAD:

https://grabcad.com/library/crafty-machines-rotruder-1