Regarding sheer webs... I like about 3/32 in balsa, and I like 'em to FIT. Fit rib to rib and covering the spar top to bottom. The comments about weight are also true. Build 'em to fly, not crash! Also, webs all the way out to the tips are next to useless. Off the top of my head, I'd say about 1/2 of wingspan is sufficient. I mean, it's there to beef up high stress points...and that isn't at the tip. Good luck...