Film hinges for the rudder should work just fine so long as the hinges are not supporting vertical shock loads from the tail wheel which would put shear stress on the hinges instead of the tensile loads for which they excel. Monokote and UntraCote bond to themselves really well. By covering the rudder leading edge and vertical stab trailing edge prior to applying the hinges, the hinges now have a better surface on which to adhere. The surface covering also helps lock the hinge straps in place. In addition, when applying the surface covering after the hinges are ironed in place, cut one piece of film covering large enough to cover one side of both the vertical stab and the rudder in one piece. Cover the vertical stab and then fully deflect the rudder and continue applying the film down into and back up out of the stab/rudder hinge valley and then continue covering the rest of the rudder. This does two things. It 1) totally seals the rudder hinge gap to increase aerodynamic effectiveness and 2) it helps ensure the rudder will stay attached even if the hinges were to fail. I do not do this for control line models because it will cause the control surface to try to deflect slightly and is a little stiffer, but for RC use with a strong servo, it won't be noticeable. To ease your mind, just install more hinges in a solid line of hinges instead of staggering them, i.e. XXXXXXXXXXXXXXXXX instead of XX XX XX XX XX. If you still have any doubts, just make a sample and then try to pull it apart. Bet you can't do it.