The rotary extruders sure look great, but it turns out they're patented, although there seem to be some ideas out there that the patent may not be completely valid. In any case, I think I will end up leaving rotary extruders for a later date. I looked into buying a rotary extruder from the company holding the patent... I didn't ask them yet whether I could buy just the extruder. It looks snazzy enough I suspect it might cost more than my entire 3d printer.
fuselab3d.com/fl300m
I had already ordered my original choice of extruder (HGX LITE) in hopes I can make it fit. I'm not real enthused about making the center piece bigger, I will look at modifying the extruder once it comes.
The big gear sticking out the top appears to be the one driven by the motor, I will try flipping the motor 180 degrees and mount it above the gear.
