Creating an indented pipe using geometry nodes

Question

Creating an indented pipe using geometry nodes

I know I can wrap a spiral around a cone using the shrink-wrap modifier but how can I change thickness / taper a curved spiral based on a formula over time using geometry nodes.

I'm trying to re-create Viktor Schauberger indented spiraling pipes. I want to test it using different equations and 3D print the different versions (see pictures below).

Here's pictures of some of the tubes:

Here's two videos of the indented pipes and how some people make it. https://youtu.be/XyOGdjWDVM4?t=1673

https://youtu.be/RlDEZT4SM94?t=2371

My thought was to:

1. Create a spiral cutter in Geometry Nodes to cut / indent the main cylinder / pipe / cone shape
2. Add a second cutter cylinder to hollow out the center of the main cylinder / pipe / cone shape.

Here's video explaining the pipe and why they do it https://youtu.be/Pv5h8alVf5s?t=1967

Ps: I'm using Blender 3.1.0 beta

I know how to generate some of the equations from a previous answered question .
I'm just trying to start simple to get it working before I add the equations to it.

Answer 1

Here is my attempt on this task. Just use the coordinates of vertices to get polar coordinate and push them into according to float curve:

6.283 is pi*2