There is no menu item to activate the zoom box. The only way to activate these functions is using shortcut keys. To create a Zoom In Box, use Shift+Middle Mouse and drag the cursor down to open a box centered on the original cursor location. During zoom in a "+" symbol appears with the magnifier cursor. The view within the zoom box expands to fill the entire Display window. Thus, a smaller zoom box results in more zooming.
Tip: Extensive zooming on the model is best done using the zoom box. Pressing and holding the middle mouse (MMB) or rolling a scroll wheel can become tedious in these situations.
To create a Zoom Out Box, use Shift+MMB and drag the cursor up to open a box centered on the original cursor location. During zoom out a "-" symbol appears with the magnifier cursor. The view in the Display window will be shrunk down to fit within the zoom out box. The zoom operation can be aborted by not sweeping out a box.
Caution: Zooming works best in Orthonormal mode. In Perspective mode (refer to the Set View Type section for further information), it is not possible to exactly reproduce the view swept out by the zoom box due to variations in the viewing angle within the zoom box.
The zoom operation can be aborted by not sweeping out a box.