Cadalyst contributing editor Bill Fane reviewed this tip from CADD designer David Gaskill will help you add dimensions to Autodesk Inventor drawings.
"Have you ever wanted to add dimensions to your Inventor drawings, knowing that you already dimensioned the model? It would be nice to leverage the dimensions from your model sketches. Right-click the view you want add dimensions to, select Retrieve Dimensions, and click on the Select Source radio button. Choose the part you want to get the dimensions from (in this case, pick the angle).
"Click the Select Dimensions button, then choose the dimensions you want added to your drawing (in this case, select the two 3" dimensions). Click OK, then clean up the dimensions by moving and spacing on the view.
"You now have leveraged the model sketch dimensions into your drawing without adding additional dimensions."
Notes from tip reviewer Bill Fane: Not only is this a valid tip, I concur wholeheartedly with it. John Walker, a founder of Autodesk, has said that we should never have to do anything twice.
A further advantage to this method is that you can edit the 3D model from within the 2D drawing. Right-click on a drawing dimension, then select Edit Model Dimension. Enter a new value and the 3D model, and hence the 2D drawing, updates to match. The 3D model file does not have to be open for this to work.
You can also move a retrieved dimension to a different view. Simply right-click on a dimension, select Move dimension, and then select the target view. Note that the dimension must be valid in the new view; you can't move the height in a front view to the top view, for example.
The old Mechanical Desktop, and many current competitive 3D modellers, automatically bring the model dimensions over when creating drawing views. Inventor can also be made to do this automatically. Select the Drawing tab of the Application Options command and check the Retrieve All Dimensions on View Placement option. This option has been available for quite some time, but has only begun to work in more recent releases. Automatically retrieving dimensions makes it less likely that you will miss applying dimensions, but note that it only brings across sketch dimensions and not extrusion depths. Unwanted construction dimensions can simply be deleted from the drawing view.