I am no stranger to booles, but this one won't work and it is driving me crazy. What am I missing here?
1.) select channel
2.) Tab -> change to edit mode
3.) A -> select all
4.) mesh -> normals -> recalculate outside
5.) select all vertices at the end of your channel and press 'f' to create a closing face (make sure you are in "vertex select" mode
6.) tab -> object mode
7.) change to "display as" -> bounds