Doug (the newbie) in my thirst for learning, I found this good video about the strength of prints “INFILL pattern and SHELLS - How to get the maximum STRENGTH out of your 3D prints” watch https://www.youtube.com/watch?v=AmEaNAwFSfI&feature=youtu.be
Pretty much what I remember from engineering mechanics class.
TLDR: 6 layers of outerwall with 15% rectilinear is the best strength and specific strength and 4 layers with 50% infill is a good compromise when considering everything including print time.