Light weight stabilator pivot: A high temper aluminum knitting needle [stub] can be glued into ply plates [on both sides of the fuselage] for the axle, and greased up for matching aluminum tubing to slide over [the bearings]. For a .40 sized 3D plane, build your balsa stick style stabilator and then sew the pivot bearings to the framework. 1/8" Aluminum welding rod that has been annealed makes a fine "elevator half" joiner. Carbon kite tubes can be used for the pivot too, just make sure they are greased where they rub.