Bars ring - Anillo de barras

English
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This is my first customizable object.

I have allowed a very wide range of values, because maybe someone wants it (e.g.: designing a cuff), but if you are designing a ring I do not recommend to use a height over 4 mm and a length (band width) over 18 mm.

The length of the ring follows this formula:
width of bands × 2 × number of bars + end bar radius × 4.
E.g.: 0.75 mm/bar × 2 × 8 bars + 1.25 mm end bars × 4 = 12 mm + 5 mm = 17 mm of band width.

These kind of rings ca