The part I focused on first was the F-779 aft bottom skin. This is a fairly thick piece (0.040") and I had decided to dimple this for rivets. The issue for course is dimpling thick material can lead to cracks if you're not careful. I spend the entire evening cleaning up holes, deburing and polishing holes with 800 grit sandpaper. From my experience on the fuel tanks...this method works extremely well.
I then dimpled the holes in the F-779 skin and examined each hole with a magnifying glass and a flashlight to ensure each dimple was clean. In the end i'm very happy with how it turned out.
