Customized version of http://www.thingiverse.com/thing:1539656

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=1539656

Using the following options:

jointDiameter = 3
rimThickness = 2
rimInnerSize = 0
armOuterDiameter = 45
height = 6.5
armInnerDiameter = 20
holeDiameter = 10
jointLength = 2
toothOverlap = 0.2
lockSize = 1
armOverlap = 2
jointDistance = 20
diameter = 50
armThickness = 4
toothSpacing = 1.06
createRim = 1
createLock = 1
toothTipWidth = 0.47
armNumber = 3
toothBaseWidth = 0.94
lockLength = 0.4
rimOuterSize = 2
createArms = 1
$fn = 100
createJoint = 0
toothLength = 0.94