Customized version of http://www.thingiverse.com/thing:968011

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=968011

Using the following options:

Infill_Strength = 33
Infill_BorderSize = 1
SunToothCountEstimate = 10
TeethToTwistAcross = 0.9
OuterWheelDiameter = 40
PressureAngle = 45
Infill_HoleSize = 2
Clearance = 0.4
Planets = 5
CenterHEXHoleWidth = 6
PlanetTeethCount = 8
Thickness = 16
Precision = 9
RingGearDiameter = 40