Creating a Helix Around a Non-Cylindrical Shape?

adam_noble

This is my first forum post, so hopefully this question is in the right spot!

I'm attempting to make a small plant pot for 3D printing. I managed to create a simple bowl-like shape by making this sketch:

And then revolving the sketch to create this:

Now, I would like to embellish the design by putting a helical design around the edge of the plant pot. However, the Helix tool seems to only want to make a helix in the form of a perfect cylinder. 
Does anyone know a method for creating a helix to follow this bowl-like design? I would then use that helix line to Sweep a sketch to create a design around the surface of the plant pot.
Any ideas?

pmd

@adam_noble I managed it here https://cad.onshape.com/documents/b7fcaa756f17e546bb49ce09/w/d41496386d8775b84ff960b5/e/58213aed8841238dfe832f9f?renderMode=0&uiState=64a1d0ebaba65a15f81ef662

I suspect my method is over complex but I created a helix based on sketch on same plane as the base and sized to largest radius and then used that to create a helix curve. This curve can then be swept into a helical surface and then I created an intersection curve between that and the outside face of the vase.