How to create surfaces / a surface from multiple non planar curves?

Hi, this is my first post,
I have created a series of curves which I have projected off a pattern I created in Grasshopper. Ideally I would like to create a single surface from these curves. Usually I would just use the surface and trim the curves out of it, but for some reason (either because the curves are non planar, or there are too many), my computer cannot complete the command, it just freezes. Any help or suggestions please?

Which command are you running? Is it Split? If so, I’d check your file tolerance to make sure it’s not too loose given the size of the small details your splitting out from the main surface. I’d also use The Pull command to make sure the curves are on the surface. From the screenshot, it looks like the surface may also be overlapping itself or degree 1 in one direction limiting the knot structure which may also prevent the Split given the size of the cutouts.

Post the file if you can and need more help.

Dear Brian,

Thank you for the quick response! I am pretty new to Rhino so please bear with me :slight_smile:
I have been trying to use the trim command but i suspect it doesnt work because the curves are non planar and the loft surfaces is? I have also tried to patch the curves independently to no avail.

I have uploaded the file, in the roof forum2.3dm (5.9 MB)

The lofted surface isn’t planar. The curves (that I tried) are within tolerance of the surface so the problem isn’t one of curves not being on the surface. The problem is simply that you have a lot of curves that you are splitting the surface with. You could try trimming the surface by using one-by-one curve (or a few at the time). I suspect that after a while the meshing will start taking a lot of time.

What are you intending to do with the result? If it is purely for illustration / visualization purposes, you could make a material that you assign to the surface where a bitmap dictates where the holes will be.


It is for a university assignment-illustrative purposes. I have opted for creating the surface with the patch command as opposed to the loft, the result isnt entirely the same as with a loft but it will work. I then split the loft which took a long time but it managed to process this command.
I attach an image of the result.

Thank you very much for all the assistance- i have learned so much from both replies!

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