this is an extruder named Loop:

• for NEMA17 stepped motor
• standart 50mm M4 fixation holes at the bottom
• RichRap quick-fit compatible
• J-head/e3d nozzle buit-in holder

it's mainly a variant of http://www.thingiverse.com/thing:28916 and Greg's Wade reloaded
what is different then?

• Tiltable M4 idler-screws really open (by 40°) and have a stronger nuts housing
• filament is closer to the M8 drive bolt than olekdh version (3.7mm center-to-center)
• oblong hole for motor positionning are wider, allowing to disangage the gear for easier assembly
• add a support for drive screw bearing surface.
• it's fully redesigned in Solidworks 2013

see instruction for more informations and changelog
feel free to make suggestions to improve this design!

instructions

• print the parts extruder_Loop_v1.1.stl and J-head_caps_for_extruder_Loop_v1.1_.stl
• remove support material around the door axis, the drive bolt's bearing cavity and on the J-head caps.
• print biggearmod_fixed.stl, smallgearmod_fixed.stl and jonaskuehling_gregs-wade-v3_idler-only.stl from http://www.thingiverse.com/thing:18379
• assemble mechanical part (do i need to explain this?-> comment)

changelog
v1.1:

• increased Tiltable idler-screws angle from 35° to 40°
• increased Tiltable idler-screws holes width from 4.0 to 4.3mm (to compensate bridging under-curved surface)
• increased clearance for door support basisi
• increased space between filament hole and drive bolt from 3.5 to 3.7mm
• reduced quick-fit plugable ends height from 5.6 to 5.3mm
  v1.0:
• initial release (part on pictures above)