as others suggestions check the hinges for movement and if youre at the outermost hole of the 6-point servo arm then the only fix to to thread the "nylon aileron control horn" (the plastic thing that is attached to the threaded rod that protrudes on the wing) closer to the wing surface that will make it somewhat similar to RCKens illustration and give you more movement. note that the aileron travel for the nexstar is 1/2" up and 3/8" down which should be plenty enough specially after you remove the droops.