Why does this Boolean Diiference fail with surface beyond object


First failure coplanar at top, then at base then solve those then still it fails, but why ?
why boolean difference fail.3dm (234.0 KB)

I love Booleans.


It’s likely because of rhino having hard time to figure out the splitting at these corners. Have you tried using Trim by curve?

Hello, this works fine in V7, if you are working in an earlier version where it fails for some reason, use Intersect, Split and/or Trim.