4 Colored, 2 Motor Extruder
This extruder was designed in Autodesk Inventor. If you have an .edu email address you can download that software for free from the Autodesk website but I apologize to those who do not own it. I have exported all the files as STEP so it should be accessible from most 3d programs. The two extruder gears were initially created with ScribbleJ's parametric herringbone gears and the larger gear was then modified in Google Sketchup to add a trap for the bolt head.
1) There is not a mounting location for the mechanical endstop that is needed for cam homing.
2) I am still playing around with the Kraken mount so that is subject to change.
3) The idlers may need a spring to force them away from the hobbed bolt when not engaged. This would be fixed by altering "top" and "idler" to allow for a spring and a bolt that runs between the two to push the idler away. This would be essentially the opposite of the Wade's Extruder where the spring forces the idler on the hobbed bolt.