Wing Flaps

Part 1 Part 2 Part 3

Part 2

Using the straight edge the hinges are positioned and mounted to the outside edge of the flap.  
The flap it then positioned and clamped to the wing.
The aileron should be mounted before attempting to position the flap so that the proper spacing can be obtained.
I used everything from duct tape to clamps to position and hold the flap in place while I got down on my knees to position and drill the holes for the hinges.
I taped several pieces of angle aluminum (1/16") to obtain a uniform gap.  The tape held everything in place while I used the hinges to drill the holes.  I sure wish I had used this method on the elevator.
The whole wing was slid out where I could get under it to drill the holes.  Use tape to hold the hinge in place until you can get a couple of clecos in place.  After that, it just a simple process to drill the holes and brush the chips out of your face and spit them out of your mouth.
Next step it a very repeatative process of position, check for clearance, sand it down and repat the process until it fits, has enough clearance to not bind when finally painted.
Finally, close it out with plenty of weight to hold it in the proper position.  The weight is not so necessary for the bonding process as it is to help remove a slight bow in the molded flap.
After close out the curved edge is stiffened with a three ply bid.  The ends are glassed as well and the flap is basically finished.