Extrude Curve on both sides in grasshopper

Hi ,

I try to extrude a curve on both side in grasshopper and it creates two surface. Is there a way to extrude it on both side but will be a single surface? I try looking on the web but i can’t find answers.

Thank you in advance

Try using two vectors at the same time

Hello Seghier

Thank you for your reply but i forgot to tell i am new to grasshopper. Can you show me how to make it?


An extrusion is the same motion as a translation (move). Just move the curve in one direction and then extrude the moved curve twice the amount in the opposite direction.

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For example

extrude.gh (6.4 KB)

Yes but this leaves an edge in the center.


Thank you for your reply. I also try to find a solution for this and we almost have the same conclusion. I am happy for that. For now I just need to extrude the line and this works for me. I add merge faces to make it a single surface. But as for the curve, it produce two surface after baking. Just like what Michael said it leaves an edge in the center. I hope this method can also be applied on curves for the future.


This is my work

You can try with tip of Michael if you want a single surface, you can also move the curve in the two directions and than use loft of other methods available to create surface

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Extrude in one direction and move the extrusion in the opposite direction using same vector with expression “-x/2” on the Move ‘T’ input.

Good day to all,

Thank you for all of your reply.

For Joseph, I like your solution better because this shorten my program. Thanks