I inadvertently left a ball peen hammer inside the wing right near the aileron bellcrank area. When we transported the wing on a trailer, the hammer bounced up and down with every
bump in the road and basically created an outward dent in the top skin of
the wing. The metal was stretched and it just kept oil canning up and down
when I tried to straighten it out.
The skin stood about 1/8" high in an area about the size of a baseball on the top of the wing. For some reason, the bottom skin was unaffected. To fix it, I took a piece of .050 thick
aluminum sheet about 4" x 6" and gently rolled it to match the curve of the skin. It was then riveted inside the wing right under the dent using about 4 or 5 flush rivets. The edge of the
piece was positioned to slightly overlap the Rib flange which gave it extra stiffness. This pulled the top skin down in the dent area until it was no longer a high spot, but was in fact now
very slight low spot. I then used some lightweight filler to fill the low spot. After primer and paint, I can't even find it anymore.