Brep/brep intersection

Hi there, i have a problem while trying to intersect two breps. They kind of flip when trying to do the correct procedure. I´ll leave some images and the file!

PRUEBA (26.1 KB)
MODELO 3.3dm (51.0 KB)

you’re intersecting one brep not two

how? You’re intersecting a self-intersecting solid

what is the correct procedure?

As you can see in this image, the two sweep surfaces intersect each other:

How to fix that is a rather involved answer… You could use an offset surface instead of the second Sweep 2 but that looks a bit distorted. Frankly, I’m surprised that the sweeps are returning single surfaces instead of polysurfaces, given the visible edges due to “kinks” in your station curves. The fact that two of your five Offset Curve components require negative offset values might be a clue.

I don’t have simple answers for you, sorry. Welcome to Grasshopper.

P.S. This replaces the second Sweep 2 with Offset Surface:

PRUEBA (21.8 KB)


Here is an effort that supplies aligned planes for Offset Curve (cyan group) so they all use the same offset value. Unfortunately, it doesn’t fix the surface intersection problem but increasing the offset value from 2 to 3.8+ does avoid that.

PRUEBA (21.7 KB)

I removed the SUnion from your orange group since it was pointless.

I can think of other ideas but as I say, it gets “involved”…

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