I'm trying to build wings for a large long range fpv craft, and I just can't come up with a strong solution to attaching pieces of the wing together so they wont fold. Do you guys have any suggestions?
In order to share the skin loading from an outer wing panel to an inner wing panel I normally just glue the edges together, (prior to folding the panels into their airfoil shape. The before folding up the wing I use packing tape, (non-stretch type on bigger designs), on the inside surfaces of the wing across the wing joint. This allows the wing to spread the forces beyond the joint line.
Of course I also use wing spars across the joint as well.
I used the same method to join the wings of my little, (ugly), stick in February last year and it is still flying without any issues of wing joint problems.