This is designed for a simple extruder to be built into the Tantillus case. Uses a nut to hold bowden tube.
Case was dremeled on the inside to fit motor flush.
I only included the part that I actually designed. The extruder arm (on the left) was not my design and is pretty standard. I did have trouble finding it again on Thingiverse so I will upload it with this when I can, but again, not my design.
This can attach directly to a motor or, as seen here, through a "case" such as the tantillus case. The plastic plate behind the drive wheel was just added for support and isn't necessary. You simply put a #8 (I believe) nut on the bowden tube and stick it in the hexagonal slot seen on the part. The small plate is very simple and I just printed a solid one out and just drilled a 2 holes. 1 for the bowden tube to go through, the other for a screw to attach it to the extruder (I actually used a computer case screw because it was easy to remove by hand). I found this was plenty of strength to hold the bowden tube in place.