Just finished my wings (minus the wingtips). Trying to recall all my mishaps and pitfalls. Some things I can think of:
1. Basic workmanship. Measure twice before you drill still just as important as when doing the empennage, otherwise you'll end up with this:
...or this:
2. Be extra careful whenever you drill, rivet, touch, or look at the main spars, otherwise you'll end up with this:
3. Take your time with the pro-seal and don't worry about using too much. Too much is better than too little. Luckily I had no leaks around rivets, but I neglected to coat all the electrical connections to the capacitive fuel sender plates, and I ended up with small leaks
through these wires, through the BNC connectors!
4. Be careful when deburring the large sheet metal skins. Don't use a grinder wheel:
5. Think about how you'll run the pitot lines through the bellcrank area. I ended up using a bracket like some other builders have done. This was after trying about three different designs:
6. Not sure what advice to give to end up with a straight aileron. I did everything according to the plans and still ended up with about 1/4 inch of twist on each:
Keep the work surface flatter than leveler than I did?
7. Deburring/smoothing out the inside of the aileron counterweight tubes after drilling. I wrapped some sand paper onto the end of a dowel and used that:
Used a similar tool to smooth out the inside of the bellcrank parts so the bolts fit through.
8. If you're going to go with the duckworks leading edge landing lights, cut those holes before riveting the leading edge to the spar. They make it easier to reach a few of the rib-to-spar rivets. I posted a write-up on my experiences riveting the leading edge ribs here:
http://www.vansairforce.com/community/showthread.php?t=156528