RE: Wings for 424?
Anybody tried "Spider Foam"? I picked up a sheet a while back but have never tried it. It is an anisotropic material.
As to Quickie wings
428 used 3/32 top, 1/16 bottom with 1/2" x .007 carbon for 18" glued to bottom skin inside.
Have also built 428 wings with 1/8" top, and 3/32" bottom, same carbon. Not much weight gain*, but a lot stiffer. Holes in the ground about the same.
#only adds about 1.6 oz with 7lb wood.