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Topology is Null in Catia surface modeling


New member
Hello everyone,

i am trying to fold one curve with folded and unfolded surface but i am getting a failure "Tolology is null"

Can you please suggest how can i loose this failure.



Super Moderator
I see that message when I have "bad geometry."

Did you Join other surfaces to the Unfolded surface? That might be a problem.

It's hard to tell what you have there, and that's a pretty complex surface to develop (unfold) into a flat pattern.

Try projecting the curve onto the unfolded surface before you fold it.