Using Reference Planes
Reference planes are construction lines that you can place in your model to establish center lines and to use as an aid for symmetrical geometry. If you add a reference plane in one view, it will show up in another. If you add one in a plan view, you can see that same plane in an elevation. This approach is a great way to build using a common reference. Also, reference planes, by default, won't plot.
The only drawback to reference planes is that they suffer from overuse. Try to use them only as what they are: a reference. To practice using reference planes, follow these steps:
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