HumanPoweredDesigner
Well-Known Member
What is the trailing edges on fabric wings and wood wings? Any fabrick wings close to knife edges, or is pencil roundness more common?
I'd think fabric shrink would damage a sharp trailing edge unless it was metal reinforced. And then with that many layers you'd have a 1/16 of an inch radius at least.
I think plywood skin could be made much sharper, but heavy, and any paint would round the trailing edge a bit. I think it would take 23 pounds of 1/64 inch birch plywood to cover the top and bottom of a 150 square foot wing plus tail. More for the rudder.
I think it might be worthwhile to have a strong, round trailing edge, and then glue on a weaker, sharp trailing edge over the round one.
I'd think fabric shrink would damage a sharp trailing edge unless it was metal reinforced. And then with that many layers you'd have a 1/16 of an inch radius at least.
I think plywood skin could be made much sharper, but heavy, and any paint would round the trailing edge a bit. I think it would take 23 pounds of 1/64 inch birch plywood to cover the top and bottom of a 150 square foot wing plus tail. More for the rudder.
I think it might be worthwhile to have a strong, round trailing edge, and then glue on a weaker, sharp trailing edge over the round one.