You can build a 40% with CA. I would use epoxy in any area that is high stress(i.e. wing mounts, landing gear blocks, firewall, stabs).
One thing I would like to clarify; epoxy is a two part adhesive. Resin is just one half and, by itself, won't bond anything. You have to mix it with a catalyst/hardener for it to actually set up. Some use a matched set of chemicals while others use one resin with an assortment of different hardeners.