This is a fairly simple tip, but one that some people might overlook. Here's the scenario: You're working on an Inventor part model. You have a feature or a group of features that you need to duplicate, but in a different orientation than the original. My example is this flanged tube, which is a simplified model of the body of a shell and tube heat exchanger. For our design all we need is the basic body, with the connection flanges located in the correct spot.
I modeled the flange in the upper left first after revolving the tube itself. This flange consists of (4) features. The flange itself is a revolution. The stem is extruded from the back of the flange "to next" to wrap it properly to the tube diameter. A cut extrusion next punches out the tube surface to the ID of the flange. Finally, a hole pattern creates the bolt holes on the flange face.
I wanted to duplicate these features, as shown, on the opposite end of the tube, rotated 180° from the original. Normal patterning tools in the part environment are not going to get this done without some extra steps. I could use a combination of rectangular and circular patterns, but I would end up with extra occurrences, which would then have to be suppressed. Mirror would have to be used twice, and would again leave me with an extra set of features. So, how do I copy and rotate this flange in one smooth motion, with no extra features being created. It's actually so easy that I'm sure you already know this one.... but here goes.
Select the feature or features you want to duplicate, either from the model itself or from your browser. Right click and select "Copy". Right click again and select "Paste". Yes, that simple. You will need to select a plane for the sketch of the primary feature. This (in my case) was the revolution of the flange disk. All of the other features were built from this one, so it's sketch plane is the only one needed. Once you select the plane, which should be the same plane the original feature was built on, you can select a rotation for the sketch. I selected 180°. Next you need to select the actual surface to attach the features to. In my case the outer shell of the tube. Select "Finish" from the dialog box, and you're done. Some features may need to be repaired if they lost references, but essentially you're there.