RE: How to Glue Flaps
When you are using CA glue, there will not be time to insert it after applying the glue. Install the tab,flap or aileron in position, place the drop or 2 of thin ca on the Hinge (what you were calling fiberglass) everything should be in place and give it a minute to wick into the materials, and you are done. After it is dry, the hinge will seem stiff sometimes. Just work the flying surface around and all will be well.
Don