Trying to mirror a face

[jmstovall]

I know there’s an easier way to do this…

I have this box that has an indentation on it. This is all correct and the depth I want:

Now, I would like to mirror that indentation on the other side, which is currently blank. But when I do select the face and run the mirror function, I get “operation failed because the resulting body would be invalid.”

Any suggestions? Am I missing something simple?

Thanks in advance!

[TigerMike]

[jmstovall]

THANK YOU! I wouldn’t have gotten to that solution on my own. Once I placed a construction axis, it was drop dead simple.

Much appreciated!

[TigerMike]

You’re welcome. Note that I sketched a vertical line at the midpoint of the side which represents the mirror plane. And yes, a construction axis works too.