you'll be surprised how far a good wash can go to improving the look of your models. And its very easy to do.
You will need some artists oil paints (raw umber and black are good to start with, get some white and yellow ochre too), turpentine or turpenoid thinner, future floor wax, and a flat-coat.
1.first paint your model. When dry, brushpaint it with future so its glossy.
2. Apply decals
3.for your shermans mix the paints so that you have a very dark brown, almost black mix.
4. when all is dry dillute your mixed oils with some turpentine or turpenoid (just dont use the natural turp.. it never dries), until you have a very dirty water.
5. now take a small brush and apply the dirty water into the corners, nooks, and crannies of your model. around hatches and bolts.
6. The dirty water fill flow around the details and make them pop out.
7 when your wash dries, apply a flat coat to your model so it stops shining.
8. as a final step you can take some yellow ochre paint and apply little dots ontp flat surfaces and then vigorously rub them into the paint in a circular motion to simulate some fading.
9, do the same for verticle surfaces, but rather than rubbing in circles, rub/pull the dot down to make faint streaks,
For the last 2 steps a little bit goes a long way so make your yellow dots very small.
Here is an example of the above techniques on my 1/48 M-10 and T-34
notice how the color differences are very subtle.
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