A direct drive bowden extruder for 3mm and a MK7 style hobbed pulley (BEARING 608ZZ)

A direct drive bowden extruder for 3mm and a MK7 style hobbed pulley. The SketchUp Make is almost completely parametrizable, so it can be adjusted to fit other hobbed pulleys as well. I have used a 11x12.5mm, 5mm bore brass hobbed pulley, because it was easy to acquire in Reprapworld .
Parted used:

1 MK7 DRIVE GEAR
1 MOTOR NEMA 17
1 BEARING 608ZZ.
3 SCREW 3MAX8MM.
1 SCREW 3MAX30MM.
2 PLATE ALUMINUM 30X7X3MM
2 THREAD BARS 3MAX60MM
2 SPRINGS 4x15mm
2 NUTS 2 BLIND 3MA
2 FLAT