I have purchased the balsa sheets, they are 1.5 mm in thickness. So the dimensions are 48"x4"x9/128"
Sheet 1 weighs 33.5 g, inconsistent grain but rigid, density: 11.26 lb/f^3.
Sheet 2 weighs 28.3 g, fairly consistent graing, but not so rigid, density: 9.51lb/f^3.
Certainly not contest grade wood. But I believe it is good enough for flying
Build process to start in... 12 hrs