How do i create a full Spiral Staircase in Catia V5?

Hello Sonny Andrews,

Find the attached file for your reference. Hope it will help as per your need.

Exactly how you will go about modeling a spiral stair depends somewhat upon what you intend to use the model for. The approach taken to model a stair to actually build will be different from making a quick model for a proposal for presentation purposes. This example : Spiral Stairs is a model of a stair that can actually be constructed. This is a typical design for a stair in a confined space. The stair is built around a central pipe column to which the steps are cut out from pieces of plate and welded to the center pipe. The other basic construction approach for spiral is for the stair to be attached to the outer wall of a tower such as a lighthouse or a tower in a castle.

Designing a spiral stair always starts with the space you have to fit the stair into. The rise in each step to be comfortable and the height the stair climbs to all determine the number of revolutions required, as I said the physical space will point you in the direction to make a practical spiral stair, an if you intend for the stair to be actually built, model the parts that reflect the way it will be manufactured.

This stair is a section of a spiral, it only rotates through 90 deg. 90 degree spiral stair but the same approach could be used to make a stair that climbs up around the outside of a circular space

I don't think you need a spiral curve, but a helix curve would be useful.

To make a Helix in CATIA, you need a Point where the curve starts, and a centerline. It's pretty simple, once you make a couple. Try it!