Ramp along 2 surfaces

[brunosisso01]

Hi there, does anybody know how can i build an spiral ramp along those 2 surfaces (i try to make it in picture n1. I have an example (picture n2) but now i want the ramp involves both of the surfaces

picture n1

picture n2

pd: i dont use grasshopper

[pascal (Pascal Golay)]

Hello- I would make a third, temporary surface and envelopes the other two in a way that you like and use that the same way that you made ramps for the individual branches.

-Pascal