helix spiral?

I have been asked to draw a spiral stair constructed of 5mm plts and a 200mm
high stringer, I have drawn 1 step and made an assm of it comprising of 6
steps but I need help with how to draw the stringer so that it can be
flattened for dxf to laser profiler. I have been playing with the helix to
try to somehow extrude a line around but not to any success

any help would be appreciated, thanks

Jules

 

I have a sample of a spiral staircase on my website. I think a few
people did some similar thing a couple of years back when there was a
similar discussion on this ng.

http://mysite.verizon.net/mjlombard/

Go to the SW Parts link on the left and scroll down.

 

I can think of two possibilities using sheet metal features for flattening
the stringer. The first is to use a lofted bend. The other option would be
to use a bend with a radius to match the stringer, then trim the profile to
suit. Sheet metal experts can chime in if more detail is needed. I don't
use either of those on a regular basis.

HTH