How to make spiral stairs Im making a water tank and to its side i want to make spiral stairs. I have tried 2 method but did not work for me both. I have add a spiral curve so that a single stair can rotate along the curve with the dupliframes. Then i added a array modifier and empty to control. I got this result the stairs not matching the side walls. And i want the result of the curve rotating in that way i want my stairs to be curved. Any suggestion

New result with empty


With screw modifier result
A suggestion is to use the Screw modifier for the railing walls &amp; keep the array for the steps. You can control the height of the screw with an empty and the diameter either by scaling in object or edit mode.