Hello!
I’m making a 3D model in grashopper and rhino for my graduation project but I have a problem.
I would like to make 2 shapes with the sweep 2 tool and the result should be 2 surfaces.
After trying 10 times I have 9 polysurfaces and once the result was a single surface.
When does it become a polysurface and when a single surface? Someone adviced me to check if my curves were overlapping but that is not the solution.
Thanks!
It would help if you can get us a 3DM file to look into…
forum.3dm (4.3 MB)
First you see 2 shapes, one of them is a surface the other is a polysurface. I tried the one that succeeded again and then the result was a polysurface :s. Tried a different shape and this is again a surface…
There are very many curves and surfaces in that file so finding out exactly what you are doing and thinking is hard…
Are you saying that with the exact same input doing that command twice in a row gives two different solutions?
As far as I could tell from a quick look, the one case has 2 single curves as rails whereas the other has two curves that are the result of 2 joined curves as rails. The latter will give a polysrf, the former a single srf.
Wim, thank you for your tip!! I indeed did twice the same with a different result. But some curves are indeed 2 curves joined together!! I will try it again!
To give more information about my project. I’ve written a script in grashopper to project a voronoi structure on my surface. If anyone is interested in this script i can upload it!
check the printscreen to see the result in a sketchup 3D model. (made it fast to check the possible result) 
Looking good!
Nobody here is against sharing 
Voronoi on polysurface.gh (12.3 KB)
Here it is!! You need weaverbird plugin.
The problem is solved btw! Thx for the help Wim!
Another option is to rebuild the curve 
Hey Amaryllida, any tips on how to export large models to sketchup succesfully? i intend to do so for rendering as i only have vray on sketchup i tried to use vray for 3ds max on work computers as export is more straightforward, but i find i miss some of the more simplistic lines and forms sketchups offers. i know this isn’t exactly the right thread, but your image intrigued me
Hi,
The structure in the picture of the initial post is exported as one .3DS file.
If my structure got more complicated and the file was around 300mb I couldn’t import it in sketchup anymore.
My solution was to export every group apart from rhino and import them all one by one in skp. This worked for me.
In the pictures you can see the final result and a 3D printed model