We are making a part on a 5 axis, that has a female pipe thread on both sides. We mirrored the tool paths from one side to the other. I got the entire assembly together and went to put in a pipe plug to pressure test, and the one side has left hand pipe threads. Took me a minute to figure out why one side went in and the other just wouldn't start.
I still think mirroring threads looks more like a bug than feature. I was just checking my colleagues drawing and the moment I saw that LH on the callout I knew what happened. He mirrored a tapped hole and put an automatic callout in. In other CAD systems you can mirror a tapped hole without the thread becoming left handed. People just expect it to work like that.
