So you've designed a part in Autodesk Inventor and now you would like to create a mirror of it so that you have both a left and right-hand version of the part file. Fortunately, in Autodesk Inventor this is a very easy process. In order to accomplish this task, we need to make use of Inventor's "derived component" functionality.
A derived component creates a part file that is based upon another file. Essentially, the source file is referenced (linked) into the new component, thereby creating a derived part. Because there is referencing between the files, a change made to the source file will propagate through to the derived part. The nice thing here is that after you have created your mirrored part, should you need to go back and change the source file, those changes will appear in the mirrored version either by re-opening it or clicking the "update" button.
Assuming that you've already created the source file, here is the process to create a mirrored version:
1) Begin a new part file
2) Finish the sketch
3) From the "Part Features" commands, choose "Derived Component", the "Open" dialog will appear
4) In the dialog, browse to the source file and click "Open" (ensure that the source file is contained within the project file as you are referencing between files)
5) In the "Derived Part" dialog that appears (see image below), click the toggle for "Mirror" and then say "Ok"
6) At this point you can add any additional features to the mirrored version that do not appear in the source file (note: changes made to the source file will appear in the derived part; however, any changes made to the derived part will not affect the source file)
7) Save the mirrored part
Closing thoughts: Derived parts are very powerful and in future installments we'll talk about some of their additional uses.