How do i create this interesting tower with staircase inside?

[kikiarchi13]

Wanted to create the tower at 9m high and the staircase, tread = 1500mm and riser = 150mm. And the entrance at first floor and the top. How do i replicate that design?

[mihai.s]

One method…

[kikiarchi13]

ah yes that method, but how do I make the lines to have thickness? And what is the ffd extension?

[mihai.s]

@kikiarchi13

And what is the ffd extension?

@kikiarchi13

but how do I make the lines to have thickness?

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