Rubberband Direct Extruder MK7 Hobbed Bolt

Requires:
1 NEMA 17 Stepper Motor
1 Hobbed Bolt (Preferably a Makerbot Stepstruder Mk7 or Mk8)
2 M3X20 screws
2 M3X25 screws
1 608 bearing
Rubberbands

The idea for this extruder drive is for a simplistic design, but one that works and doesn't use too many parts you have to find from elsewhere. Most direct extruder drives require extra screws, washers, springs and nuts but this one only requires the use of rubberbands. Do not add too many rubberbands, as this will cause your motor