Topas Try Me's: Spiral Stair Case (continued) 

Now we get to make the steps jump out with the extrusion tool.

	5. BUILD -- COMPLEX -- EXTRUDE  Choose your object, and extrude at an angle of 90 degrees, and a depth of .45 ft.  Holding the Shift Key will assist in getting exact 45 and 90 degree angles.  Also, again it's probably best to key in the depth rather than poking the little up and down buttons on the selector.
6.     Now you have a shape, but you need the center pole that spiral stairways are structured around.   Create a simple circle. (BUILD -- SIMPLE -- CIRCLE)  BUILD -- COMPLEX -- EXTRUDE the circle at 90 degrees to any length.  MODIFY -- OBJECTS -- ROTATE the circle (now cylinder) on the X-axis by 90 degrees.  7.    Now MATCH the pole under the MODIFY -- OBJECTS menu to the stair case. Be sure to select CENTER TO CENTER.  Note -- The object selected first becomes the 'base' object that the second object gets matched to.  8.    Scale and stretch the pole as necessary so that it fits the length of the Stairway, and also fills in the center gap.  Special Thanks extended to Jennifer at Crystal Graphics for giving us permission to use this information that first appeared in the Spring/Summer 1995 Issue of The Topas Times.