Ditto the Vaseline or oil to lube the hinge. The following is for installations in a built-up structure or a traditional foam wing with balsa strip at the hinges: I use long curing epoxy and a syringe. I drill the holes almost too small for the size Robart hinges. With the barbs on the hinges, you almost don't even need to glue them in if the hole is tight enough and the balsa is hard enough. I get a ton of epoxy in each hole, then push in the hinge. The key here is that you want to then orient the part such that the epoxy oozes down and forms a washer around the portion of the hinge point that protrudes out of the internal surface of the balsa strip. In other words, if this is the stabilizer portion of the elevator hinges, stand the airframe on its tail (nose-up) for over-night cure. That epoxy washer locks it in so that a 200 mph Earth impact is the ONLY way that thing will EVER separate from that balsa, EVER!