As I mentioned above, there is a solid balsa block under the horn ply plate. With all the talk about hardware, and flutter problems with this Extra, I have made more modifications. I stripped off the ultracote on my wings and cut my CA hinges on my ailerons surfaces only. I added balsa blocks for Robart hinge points. Total of 6 hinge points will be installed. I then proceeded to guage out a bit of the balsa sheeting and into the horn block on the top of the ailerons. I chiseled out till I had about 1/4 of my rocket city screw showing. I then added a wood dowl piece about 1/4 thick by 3/4 wide to catch the exposed part of screw. Which like I said is already incarcerated in balsa block with epoxy, and probably would have been ok anyway. I epoxied in this dowl piece around the screw and now I have no doubt this will be sufficient! I will next do the elevators this way, although I will keep the CA hinges in those. Man, I hope this airplane is going to be worth it!