Offset (SOLID) surface = untidy surface

Hi there, i´m struggling with this surface, when i apply this command it becomes one with loads of mistakes and i cannot go any further.
Is there any way to make this surface without this happening?




COSTILLAS.gh (24.4 KB)
COSTILLAS.3dm (139.2 KB)

Solid offsets are really unreliable. I think it’s because there are so many different conditions that can happen in a polysurface, which makes a one-size-fits-all process hard to perfect.

Are all of your polysurface faces planar? sometimes in that situation, if offset doesn’t work, it’s possible to offset the faces individually, and extend them in all directions and use boundary volume to get the new solid.

Your GH file fails to reference the Rhino file geometry? I tried guessing at R1, R2 and the section curves for Sweep 2 but one of the rails (the bottom curves?) needs to be flipped. Correction: reversing the list of section curves fixes that problem. But the “Closed Brep” is corrupted with self-intersections.

Then I noticed that your cluster SrfOffsetSolid is password protected so there’s nothing I can do with it anyway. It’s the holy grail if you can make it work, good luck.

This is a different way to get a solid that doesn’t use offset surface. The idea is create section curves that describe a true cross-section of the intended solid and then sweep (or loft) them, finally adding Cap Holes to close the ends. The section curve params are declared explicitly to ensure their proper sequence. I internalized the curves I used and didn’t bother trying to understand what your big orange group is doing with this solid. Don’t know why your Rhino file references failed?


COSTILLAS_2020Aug18a.gh (20.1 KB)

I used a messy Offset Curve approach to make the sections for Swp2. If they are all the same, it would be better to draw one (or create one with GH) and either replicate it or sweep just one section. As is, the result is not very “fair”, in part because the middle sections are likely mis-aligned.

P.S. By disabling 3 of the 4 section curve params, you can easily see a much more fair result, as expected. In addition to possible mis-alignment, there was a subtle twist in the sweep of four sections.

Thanks!! I´ll try it!!!

Wow thank you very much to take this time to rebuild the geom, I´ll try it now!

I’ve spent a lot of time chasing that holy grail of an offset polysurface, always failing. This is my typical work around. Please don’t miss the “P.S.” I added to my post.

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Yeah reading trying to put everything together so as to get the result i m looking