Customized version of http://www.thingiverse.com/thing:45117

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=45117

Using the following options:

Wall_Thickness = 3
Knob_Fill = 1
Number_of_Rosettes = 6
Chamfer_Size = 1
Rosette_Offset = 3
Rosette_Radius = 6
Knob_Thickness = 6
Knob_Type = 1
Thread_Size = 5
Knob_Diameter = 40