I cannot avoid naked edges with EdgeSrf command

I am very beginner in Rhino.

I am following some YouTube tutorial and stuck at following step.

It is the step when I should use the command EdgeSrf for two curves as shown in the following image, one is of the surface edge, and the other is just a line that kinda closes that edge:
2021-04-11 16_46_17-Window

When EdgeSrf finishes it makes a surface that looks like this:

2021-04-11 16_46_27-Window

Can anybody teach me what is wrong I am doing?

Plus, whatever I do to solve that problem (ex: using Rebuild command), it ends with a surface with naked edges, so how to avoid naked edges with EdgeSrf command in my case?

I thought to attach rhino file in case it helps better.
10-3d-11042021.3dm (676.0 KB)


Hello- try PlanarSrf with that input.


@pascal Yeah PlanarSrf solved it.

What is the different between EdgeSrf and PlanarSrf? When to use this and not use the other command? And the guy in the tutorial used EdgeSrf and it worked well, is there an answer why it didn’t work with me so I can learn what I did wrong from the beginning?

Also I got one issue, the next steps are to join this surface with the big one, and use Cap command.

Here is the result of joining both surfaces:

When I do Cap command, it says:
Unable to cap 2 objects. The openings did not have closed, planar loops of edges.

Sorry I couldn’t learn any from the error message because I don’t understand it yet.

Hello- please see

But, for the objects in the sketch, I would use SubD surfaces.


Alright @pascal . Thank you :pray:. and I will also check SubD surfaces.