BooleanUnion not working, how to debug?

Hi everyone,

Quick newbie question: how do you know the reason why BooleanUnion “is not working” when two closed polysurfaces are clearly intersecting? I’m attaching a file where I would like that the small piece (top) unions the big one to have a flat surface at the top. I’ve always used BooleanUnion successfully but don’t know what can I do here?

Thank you in advance.

BooleanUnion.3dm (6.4 MB)

Hello- these objects intersect within tolerance of the edges all the way around- not an ideal situation for a Boolean operation - are you just looking to clean up that top like so?

If so, you can just create new surfaces, say by lofting across matching pairs of edges.

then Join it all up and MergeAllFaces (MergeAllCoplanarFaces in V7) to clean up.

-Pascal

Thank you!

The reason why I had such a complex surface at the top is that I’m familiar with Patch, but it’s good to explore other options, definitely! I’ll check, thanks again.

EDIT: yes exactly, the reason is that I need planar at the top, given that the wing will be planar as well, so they match perfectly.