The way one old time scratch builder (Mr. Matthews) told me how to figure out wing loading goes like this.
Weight in lbs. x 16 x 144 divided by wingarea in sq.in. will give you your wing loading. If your not convinced, find a tower hobbies magazine that tells you weight in pounds, wing area and
wing loading and give it a try, I think you might be surprised.
Example: Midwest 1/6 scale AT-6 has an 83" wingspan, weight is 15lbs. and wing area is 1000 sq.in.
15x16=240x144=34,560 divided by1000=34.56oz/sq.ft.
It works every time.