A modified Greg's Wade extruder to directly take the Geeetech all metal hot end without any adapters. Be sure to use a fan so you don't overheat the extruder. This one should work with a 30 mm fan: http://www.thingiverse.com/thing:389444 The hole was deepend a bit for more Z with this longer extruder and the screw locations were moved up a bit to accommodate the Geeetech dimensions. The Gears and Guider are included as a convenience and have not been changed.  Instructions: I recommend printing in ABS or Nylon for heat resistance. I printed mine @.2 LH with a .35 nozzle with 40% infill and 4 parameters. Clean out the first part of the holes to 3mm while leaving the second half for the screws to tap into as with the regular jhead installation. Printed on a MendelMax 1.5.