Occasionally I get questions about the difference between SOLIDWORKS Projected vs True Dimensions. To demonstrate the difference, I’ve created a drawing of an awkward plate, which was modeled up at a 20° angle. I mostly did this to demonstrate the concept in an orthographic view as well, but you may or may not have your own reasons. Please watch the video illustrating the difference between Projected and True dimensions:
When to use projected dimensions
As a rule of thumb, you would typically only use Projected dimensions on an orthographic view and typically only use True dimensions on an isometric view. There is no “one-size-fits-all” option, which is why it gives you the choice.
For your reference, I’ve pasted screenshots of the Projected and True Dimension drawing sheets below: