How can I create an intersecting helical loft of a profile to create a volute for a stair handrail?

I am attempting to create a spiral/helical loft or sweep in order to create this:

I have a 2D sketch of the profile to create this from, like in the 3rd pic. How would I go about creating this part? every time I try I get errors like it has intersecting geometry and solidworks wont create it. Maybe I am going about this all wrong, how would you do this?

SolidworksParts And Features