Customized version of http://www.thingiverse.com/thing:543772

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=543772

Using the following options:

outerRadiusOfLargeWheel = 3.2
outerRadiusOfInnerWheel = 2.8
cutoutRadius = 0
topLandWidthOfLargeWheel = 0.2
innerRadiusOfInnerWheel = 1.8
depthOfLargeWheel = 5
numberOfTheetOfInnerWheel = 9
spaceWidthOfInnerWheel = 0.2
innerRadiusOfLargeWheel = 2.2
depthOfInnerWheel = 0
topLandWidthOfInnerWheel = 0.2
numberOfTheetOfLargeWheel = 8
spaceWidthOfLargeWheel = 1