Aside from the DAK armor I'm making at the moment, I'm also working on a Matchbox 1/76 Sherman Firefly. The model has been primed black and basecoated with Tamiya Olive Drab, which IMHO is a bit greener shade than most olive drab paints I have. A layer of Acrylicos Vallejo Olive Drab -- which is a darker olive green -- was then painted on. A couple of black ink washes were then applied to run into the creases. The first wash was a general application of diluted black ink. The next was a more area-specific application of a purer black. The model was then left to dry for a few days. I started brushing the Acrylicos Vallejo Olive Drab onto the surfaces, cleaning off and touching up areas were the black ink shouldn't be and being careful to preserve the ink that dried inside creases and crevices. A slightly lighter shade of this color was mixed and lightly drybrushed onto the raised surfaces and edges. An old flat brush was used to blend in the edges with the dark...
My adventures in scale modeling