Simple string guide for window blinds or shades. Cut it in half after printing to get both sides. It has a diameter of 3 mm. For different diameter (D) values you can simply scale the model in your slicer by using the factor

F = D/3 (mm),

in which D is your required diameter in millimeters.

Printing note: I managed to successfully print the model as it is, without any supports.

Model units: Millimeters (mm).

Infill: 100%

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