clarification of how to design, size and build a metal spiral staircase.

excuse the question from a lassic artistic blacksmith, how should you proceed to design and size a metal spiral staircase, the various parameters the step of the spiral steps the handrail railing, the central pillar, the steps and the fixing system? thank you sorry if I disturbed you.



https://www.alfredoneri.com/progettazione%20scale.htm





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