So I'm working on my first map, and I've been having a bit of trouble with the pipes. I'm making a path similar to the pipes in 2Fort, and I can create the brushes themselves just fine, but I'm not sure how to make the pipe fit cleanly into the wall. I'm not sure how to explain it, here's a picture of what I have: Essentially, I want to know how I can make a wall that goes all around the pipe without blocking entrance into the sewer. If I'm still not being clear enough, the pic below is an example of what I'm trying to create. I haven't been able to find any tutorials that explain this particular brushwork, so if anyone could help me out, that'd be fantastic!