RE: trailing edges
I agree with Jan. Full scale wings have sharp trailing edges. Ever walk into a Cessna wing?? Look for a corregated crease in your forehead! Lately I have been sandwiching the trailing edge with balsa and thin G-10 phenolic sheet. That way you can get the sharp edge required. And it's bullet-proof and will not ding or fold over as unsupported edges do. Regards.