Adobe Illustrator: Creating a plastic/three-dimensional helix

Question

This question is based on a question I have posted here previously: Adobe Illustrator: Creating an helix

In Illustrator, I am able to create the following tube-like shape, by creating a blend out of two circular shapes by giving them a gradient stroke:

How can I turn a tube like this into a helix? In other words, I want the tube to follow the path of a helix.

EDIT: As one of the commenters suggested, replacing the spine of the blend with the path of the helix actually works fine, here's the result:

Answer 1

If both ends of the spiral are hidden behind other structures, then a pile of simple identical rings can be a plausible fake spiral:

Used ring is 3D revolved ellipse. To get it tilted, do envelope distort. To keep tens of rings light for the computer, make one and use it as a symbol.

This job is much easier in a proper 3D program, but the created scenery is not available for Illustrator as AI shape, only as a bitmap image. In real 3D there are no difficulties with spiral's ends and viewing angles.