Customized version of http://www.thingiverse.com/thing:16627

Created with Customizer! http://www.thingiverse.com/apps/customizer/run?thing_id=16627

Using the following options:

idler = 1
pulley_b_dia = 25
retainer_ht = 1.5
nut_shaft_distance = 2.5
additional_tooth_width = 0.2
nut_angle = 90
retainer = 1
additional_tooth_depth = 0
pulley_b_ht = 8
teeth = 60
idler_ht = 1.5
m3_nut_hex = 1
motor_shaft = 8.4
profile = 12
no_of_nuts = 2
m3_nut_depth = 3
m3_nut_flats = 6.1
m3_dia = 3.2
pulley_t_ht = 12