Blend curve along surface

I’ve added an example problem to clarify my issue.

In “Example.3dm” you can see the surfaces I’m trying to blend. Before I do this, however, I’d like to adjust the surface edge of the bottom surface. My best guess on how to do this would be to use the BlendCrv tool on the surface edge twice with tangency enabled (see images). After using BlendCrv I then have to project the blend onto the surface to create the new edge that I will be blending from. I was wondering if there was a tool in Rhino which would let me make these two steps simultaneously. So maybe a BlendCrvAlongSrf, or maybe another tool which would let you reshape the surface edge or surface edge curve along the surface.

EDIT: Maybe a project on surface preview option could be very interesting for the BlendCrv tool?

Example.3dm (88.9 KB)

Hi Luc - try this - Make a curve that has the shape you like, in 2d on the CPlane in this case should work fine. From the top view, or top to to the CPLane if that is not the world top, Trim the hole into the surface with this 2d curve. For more control, Project the curve first, using History, and then edit the 2d curve until the projected one looks correct, then trim with the projected curve.

-Pascal

Hey Pascal, that works. Thank you!