Wanted to replace the current extruder with a more open design and turned 90 degrees. Working great. Video in action https://youtu.be/UUGyNforwh4 Using original brass gear - https://youtu.be/gmL29dGagAo Credits: E3D Hotend Model - http://www.thingiverse.com/thing:341689 Basic Extruder - http://www.thingiverse.com/thing:183982 Carriage Mount - http://www.thingiverse.com/thing:408818 Nema 17 Model - http://www.thingiverse.com/thing:67561 E3D Mount - http://www.thingiverse.com/thing:512452 Update: The extruder will print without any supports but may need to be rotated. The part that attaches to the x-mount should be laying flat. Print out one of each. Use various M3 nuts and bolts. Good idea is to seat the nuts before assembling anything. Uses 608zz skateboard bearing and M8 gear. Should work with most any gear driver and bearing. Check out the pics for how to press the bearing rod into the bearing. Metric bolt source http://www.trimcraftaviationrc.com/index.php?PHPSESSID=-0pPdMw,AdTgXR3IT14jy0 thanks to http://www.fabric8r.com/forums/showthread.php?2454-Metric-bolts-nuts-Source-in-US&p=23873&viewfull=1#post23873