If I totaled the time of paint only, it would probably be about 4 days, 5-7 hours a day. I did a couple pieces at a time, so I didn't have to keep mixing paint. I wanted it all to match and be from relatively the same mix batch.
copied from the Legion boards:
The armor is weathered first, per Kev's tutorial. The main shapes are taped off. I tried to make them connect in some way. No pattern, just random directions and shapes, trying to focus on the right angles of "digial camo." Shot that with a rattle can of Model Masters "Euro 1 gray." Untape it. retape some larger shapes that go over the existing work and tie a couple of shapes together. Untape that. I rub the whole piece with a 3M scuff pad between each step to help blend and spread some of the green tint from the gray color into the white.
Then it's all airbrush shading and template work. The greenish color is called dunklegrun 17. It's green, but I mix a little of the Euro 1 with it to tone down the green. I have 3 thin cardboard templates with various shapes and angles cut into the perimeter. I use it in a way similar to that of Mike Lavalle. He does realistic flames on hot rods and custom cars. If you've ever seen his work on Rides, or Overhaulin', you kinda get an idea of how it works. During the shading, shapes will start to reveal themselves and I just shade and build off the new shapes...........basically.