Guys who fly radio control ( most relevant to the "discus launched gliders"
1.5M or less span launched by holding a wing tip and spinning prior to release) typically use a type of tape specific to the application. I've also just used clear packing tape on 10 foot wingpan sailplanes ailerons and flaps. Mine always have some sort of finish on the surfaces - either Monokote or paint. Remember that any tape will need to be replaced eventually - UV will eventually ruin almost all adhesives - and you really don't want any residue left over that has to be sanded off or want tape that will remove a lot of wood when youu replace it because it has a tear or crack at one end.
There is another stype of taping called "book hinging" that is somewhat better and more difficult. It involves several small pieces of tape assembled to have several 1 to 3 inch pieces of tape that alternate going from bottom to the top. They are somewhat painful to assemble and install neatly, but keep the LE of the control surface straight and snug along the TE of the surface bay while maintaining low deflection force. I use this even on rudders so that the force at the control horn does not misalign the surfaces when deflected. It helps to prevent hysteresis on the control surface and is quite effictive at doing so.
You could aslo use a standard model airplane hinge, which is just a piece of plastic that is notched onto the wing and aileron. Search for these HLH847 at
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These are covered with CA friendly fibers to make them easy to install. The only disadvantage of the hinges is that they do not seal the gap and will introduce some air leakage from high pressure to low. I've used these as well.