Modeling a spiral using a helical sweep tool

[luke123]

Hello

I am trying to model a spiral shape that has a variable profile, variable pitch and a variable section.
The first two are no problem using helical sweep tool, but there is no option for varying the section along the way?
Can someone shine a light on the issue? I am using Creo 2.
Thanks

This is what I have so far.

 

[srieger]

You may be better off just making the helix then doing a revolved cut to taper the helix on the ends. You may be able to do it using a graph feature but that may be more complicated than its worth.

 

[luke123]

You may be better off just making the helix then doing a revolved cut to taper the helix on the ends. You may be able to do it using a graph feature but that may be more complicated than its worth.

I think I have found a way. I revolve a shell of the profile of the spiral. Then using the helical sweep tool I make a helix using only a surface.
Using intersect tool with both features marked I finally get a sketched curve that I can now use with the good old sweep blend tool.