Spiral Staircase

geometry. If you paid no attention in highschool you will wish you had.

Do not use the staircase component, you need to swivel every tread which is just a plank of whatever tread height you can climb smoothly. This is trial and error as it depends on ceiling height and climbing on inner/outer radial side. The total height divided by rise is the number of divisions you need in the whatever circle angle you need to turn and from that you get the angle increment to use on the steps.

I fly because it is easier to snap and rotate on the way down. Use the central axis as your snap line.

You will probably need to remake it several times to get it right. At same point you will say why did I not make space for regular stairs with landing on corners.

I use square rounded block at 2.0 wide x 1 deep x .3 tall. I place one down then modular snap to the bottom right corner and put my rotation at 15 degrees. Rotating 15 degrees each placement as I go up. Maybe I’ll make a tutorial😁

Roen give you the easiest solution, but Krazmuse is right too. If you want to do something precise, geometry is the only option. If you're not afraid by numbers, I made a spreadsheet a long time ago to make this step easier. I share you the last version of this file in attachments. They are instructions inside but it's still a bit complex to use, feel free to ask for help.

P.S. red51 It's possible to allow direct sharing of LibreOffice files (*.ods & *.odt) on the forum? Actually, I must zip a 39kB file to do it

Axel5616 In the past I've used small, square blocks and snapped wooden planks onto them. You have to rotate the small blocks by ca. 20 degrees each time until the desired height is reached. Since the wooden planks dock in the middle of the square block, the distance to the floor above must be taken into account. The small block sometimes needs to be rotated so that the snap mechanism works correctly and the steps are usable.