Smooth surface with curve network. Removing Crease?


Can anyone assist me with getting a smooth surface with network of curves? Or possible removing a crease?

As you can see, the " Slash " causes the crease once the profile is swept acorss 2 curves due to the transition.

Also, why when using surface from curve network, corners end up rounding out?

Thanks for all help! :}

Hi Josh- please post the curves.

NeworkSrf does not have the ability to make kinks in the surface - it always refits the input into smooth curves.


Hi Pascal, and thank you for your message.

The curves are in the first pic ( show in red ).

I think what Pascal would like is a .3dm file with the curves so he can play around with them to see what’s going on.

With a 3d program, 3d info is far better than 2d info for diagnostics! :smile:

Ahh. Thank you for the clarification!

Josh W

Hi Pascal, I posted the curves ( Thanks to AIW for clarification! :} )

super appreciate all the help!

  • Josh

curves.3dm (157.8 KB)

I don’t see any kinks in the surfaces. But the corner cusp is significantly affecting the shape. Consider creating a larger surface without a cusp, and then trimming back to the surface you want.

Also, the two side polycurves are not great; too many control points close together with some abrupt twists. Simple curves are better than polycurves for creating surfaces. You can get very close to the same shapes with much simpler curves. The simplified curves in the attachment deviate less than 0.0055 from the original curves. I created them with FitCrv.

curves_DC.3dm (383.2 KB)

Hi Josh- I don’t know if this gets close enough to what you want but have a look- the surface is overbuilt, so to speak, and then trimmed.

  1. Mirror your curves.
  2. Make a BlendCrv across the top and Join it to one side curve (the long green curve)
  3. Add two lines, (Cyan) , changeDegree to 2 and 'pooch them out a little" by moving the middle point. (Gumball works well here for keeping control).
  4. With History on, make a networkSrf from the green, cyan and the blue line at the bottom. Your top circular curve is not used in the network.
  5. With History on, Pull your top curve (white) onto the surface (result is red).

Now, noodle the middle points on the cyan curves until the red curve closely matches the white one. You can adjust these further in the attached file.

curves_Josh_PG.3dm (213.1 KB)


Hey Pascal, Thanks a ton for the assistance! I’ll give it a go and see what
i come up with.