Boolean difference failed - 2 closed polysurfaces


I cannot do boolean subtaction of two closed polysurfaces which are stritcly composed only of planar surfaces. I need to bite off the piece of excavation into terrain.

It is a bit complex geometry but i think this should be possible.

I had a “malicous file” warning when I tried to download your file. It may be a false alarm but I can’t be certain.

You can post the .3dm file directly by uploading using the vertical arrow above where you type a post, or by dragging the file to where you type a post.

it looks like you used mesh which you turned into nurbs, maybe try with mesh booleans first. other than that, when you intersect the two objects you see that at this position there is a part where the surfaces would get very thin, which i assume could be causing the boolean to fail if the distance falls out of tolerance.

edit: there are also other parts which could result in very thin surfaces. when you follow the intersection around, for example above close to the yellow marking the intersection runs very close to the edge of the surface. such results can hinder a boolean to work either. working with complex polysurface and having random complex surfaces cut in is always a lottery.

i can assure you its safe maybe its just because of the site on some suspiscious list but in slovakia its a common file exchange site. the file is 38mb i did not want to post it here.

well it is a strange link, i had to use a different browser to download it since safari would not even download it, after i clicked i got served another field to click which ended in an endless loop, so i used firefox in the end. no idea if its infected.

Hi Ivan - your point-of-interest in this file is about 1300 km away from the origin in a millimeters file.
When you bring those to the origin, the BooleanDifference seems to be working fine.


yeah origin is somewhere in the baltic sea and this project is close to poprad, slovakia :smiley: i will do that closer to the origin and move back … 10 digits from precision are lost just due to the distance