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I have some hanging lamps above my diner table but they're in the way when I want to fold clothes. I designed this cable shortener to be printable without supports, be elegant and to use  little material. My cords are 6mm but the design should work for both thicker and thinner cables. 

Please slice the .step file! This has perfect circles. I added the .stl because Printables can display this. 

I attached the Freecad design so if you do need to adjust the profile you can. The model breaks if you increase the radius of the circles because the profile sketch does not align with the circles that define the revolution anymore. I did not feel like fixing this, but if you ask nicely I can adjust the design for smaller / bigger radius.