I can't remember where I got this one, but it works every time. Instead of sanding the wing saddle to get a perfect match to the wing try this...

1. Cover the wing where it will contact the saddle with seran wrap or whatever that thin plastic stuff in the kitchen is called.

2. Mix up a batch of 30 min epoxy and add some micro balloons in a 2:1 ratio. 2 parts MB to 1 part mixed epoxy.

3. Lay a bead about a 1/8 inch bead along the saddle, too much is okay here.

4. Attach the wing to the fusilage using the rubber bands, bolts, or small sand bag.

5. Let it sit about an hour or so till the epoxy sets but is not yet rock hard.

6. Remove the wing and plastic, trim the excess, and voila!, a perfect wing saddle.

Key things to remember... Do this before covering, and don't forget the seran wrap. Guess what happens if you forget about the seran wrap.

I still can't remember who I got this tip from, but if you're still out there, Thanks again.