This thing works great so far, It can turn all the way back on itself with 16 joints, that is what I would recommend printing right now (first test two joints to make sure the fit works on your printer).

I am working on a new design for the locking nut that will be much more forgiving for different printers from entry level all the way up to a $25k stratasys. Stand by for that, I don't want to release my new design until I have had a chance to fully test it.