CAD (Computer Aided Drafting) is far better than manual drafting for one simple reason. With manual drafting you must know more of the properties of the line before you draw it and the precision is only approximate: no information can accurately be gathered from analyzing the relationship between objects because of the lack of precision. With CAD there is no guessing, no approximate, no about.
When I was teaching myself about groin vaults the only math available to discuss the constantly changing aspects of the ellipses was calculus. Nope, not this guy. I wanted to know if it could be drawn in CAD and was it accurate. I wanted a practical application for constructing a current architectural style instead of just "guessing" at it. CAD not only was the practical application but the proof of the ellipses was graphic and not just mathematic.
One of the services I offer is CAD drafting for any project you may have: houses, roof systems, remodels, cabinetry, decks, rails, fences, exterior stairs. Structural engineering is available by California state licensed engineers. Contact me at info@CaddyShackProductions.com.