I use elmer's white glue when i built and need balsa to balsa bond. white glue is not fuel proof or any other liquid for that matter. but it makes for great strong bond. for anything else that will take alot of stress such as landing gear block or wing spars I use epoxy.
good luck.
Oh I had a 4 star 60 that I used white glue to build with. I had her for over 2 years had over 175 flights, on one flight I took her way up, power dive vertical down and just yanked on the elevator (wanted to see what would happen) saw the wings flex with no damage. mind you I only did it once....