This is another nice design from maker Chris Call. I printed this with black PLA, then tapped the cap screw holes to 3mm and reamed both bearing openings to 15mm. The support material was a bit time-consuming to remove, but worth it... to get a decent extruder on the DaVinci 1.0 Pro. I purchased an Mk8 extruder from Sintron on Amazon.com ($50), and it seems to be of good quality (better than that of the TAZ-5, seeing as how most of the parts are metal instead of 3D-printed). I'm still waiting for 15mm linear bearings, 3mm screws, and hardened 8mm shafts... otherwise, I'd have finished project photos posted.