Customized version of http://www.thingiverse.com/thing:54395

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=54395

Using the following options:

hole_diameter = 10
build_plate_manual_y = 100
build_plate_manual_x = 100
res = 50
height = 12
cog_base_width = 10
no_angle = 20
cogs = 30
cog_length = 20
cog_base_height = 12
cog_tip_width = 4
tip_height = 12
build_plate_selector = 0
internal_diameter = 42