I chose to use hinges to attach the two wingtips. The obvious benefit is the exceptionally clean look of not having numerous screws on the top and bottom of the wingtip. A second benefit is how quickly you can remove the tips. The downside is it does take more time and care to fit the tips well. Another downside I discovered is that the trailing edges have a slight amount of movement. Both tips have this problem. The trailing edges can be deflected up and down about 3/16" to 1//4". Obviously, this is not acceptable. I discovered that the slight gap that exists between the hinge's rolled links is causing the slop. I put a small c-clamp on the aft end of the top hinge and the deflection disappeared. So, I began fabricating a sort of bridge that will lock the two hinge sides once the pins are installed. I fabricated a spacer deep enough to clear the hinge's rolled links. My plan is to permanently attach one side of the bridge to the bottom wing side of the hinge. On the tip side of the hinge I'll install two #4 screw nutplates. I'll simply install two countersunk #4 screws on the tip bottom near the aft end. This should be sufficient to lock the hinges from any further movement.