Thinking In 3D
Before we dig into 3D design in a CAD program, let’s take just a moment to think about 3D objects in general This way of thinking is a great foundation for thinking about objects in 3 dimensions. An orthographic projection is a way of representing a 3D object in 2 dimensions.
Let’s take a bird house and look at its orthographic projection.
The elevation is the front view, it’s what we see if we look at the house straight on. If we rotate to the side, we see the side view. One more rotation and we see the back.
 Let’s go back to the front elevation for a moment. Our next view is called a plan or, in the case of a house, a ground plan. This is how you need to first imagine your design in 3d before designing it.