Thanks Dan, you're absolutely right, what I want is slotted flaps. I'll have to look into doing it with control horns. I was planning to have the hinge points sticking out the bottom of both the wing TE and the flap itself, putting the "elbow" of the hinge down below the surface of the wing, much like the control horn method, but I like your idea of using control horns even better!

Thank's for setting me straight on how the flap-TE interface should look, for some reason I was thinking the slot should run the other direction, but obviously I was way off base. I've got a much better mental image of how it should all go together, now.

While I'm on the subject, how wide relative to the wing chords should the flaps be? The plan I'm using a starting point for my Astro-Piglet shows the ailerons being ~25% chord width, and they inhabit the outer 6 of 11 wing bays. I was planning to put flaps on 4 of the other bays (leaving the inner-most bay of each wing available for attaching the wing to the fuse). Should they also be 25% chord, or should I make the flaps larger?