This is not rocket science but it worked really well to have precision hinges on my FuntanS 40 ARF. Most of it I got from other people.

1) Carve out hinge slots to proper depth with a the .010 feeler gauge. The #11 hobby knife was a little too thick and I didn't want to make the slot too sloppy. Drill a hole in the center with 3/32" drill. Clean out slots again after drilling. Do this to both wing and aileron slots.
2) Put hinges in wing slots making sure they line up with control surface slots. Lock them in with a small drop of CA. Let dry for a few minutes.
3) Slide aileron onto hinges. Use .016 feeler guage to set gap at 1/64th of an inch all along hinge line. Make sure the aileron has a 1/16 inch gap on the root side so it doesn't hit the wing during deflection.
4) When control surface is perfect, put one drop of CA on each hinge to lock in the position of the aileron to the wing.
5) Now put 5-6 drops on each hinge to make them full strength.

Man I tell you, this gave me perfect hinge line gaps and the hinges are very strong as well. I just don't like having my hinge gap be a guessing game every time I assemble an ARF. You can put a feeler guage all along the slot and it's dead nuts perfect. They move very smoothly too.

And hey, NO PINS NEEDED !!! (they never work for me).

Joe