New Wade extruder for Skeleton 3D

After building Catastrophe's fantastic little Skeleton 3D printer , there was 1 thing about the printer that didn't work to my satisfaction: the extruder.
It works perfectly wel for PLA but for ABS it jammed regularly.
This is because ABS is both softer and more slippery and the extruder was designed and tested only for PLA by its designer.
I asked one of my best friends , and retired teacher in design with Inventor, to help redesign and draw in inventor a new extruder.This one should be based on a Gregs-Wade extruder, and placed on a adapted X-Y carriage. We also added a 30mm fan to cool the J-head.
The long screw, next to the J-Head in the drawing, serves as a support, to atach the wires for the heater cartridge and the thermistor with tie-raps.
The gears used are the standard Wade Big and Wade Small from the REPRAP wiki page of the Prusa Mendel i2, but we changed the gears a little bit to make them more solid. I'll add them to be complete.