While working with Nathaniel trying to print parts for my Tantillus, I have seen him dismantle his extruders on a number of occasions. The reason for this seems to be that the hobbed bolt is a bit of a week bit in the design process. Since the Tantillis uses a Bowden tube rather than the extruder motor being mounted directly above the hot end it is easer to redesign or replace the extruder motor mechanism. One I have found does away with the Hobbed bolt and replaces it with a Dremel High Speed Cutter bit #196,
I will have a play with the No-Hob extruder in CAD and try to make it work with the Tantillus’ Bowden Cable.