Jurgen Mares explains how he uses hairspray to great effect!
A technique I sometimes use to give a vehicle a winter whitewash scheme is known as the 'hairspray technique'.
It's an effective way to mimic a chipped and worn appearance over a vehicle's base colour. The same technique can also be used to depict a rusted vehicle by substituting the whites for rust tones.
Hairspray is then sprayed over the entire model and left to dry. I gave it two coats just to make sure everything was covered. The hairspray you use can be the cheapest, unscented own-brand supermarket type.
After approximately 10 minutes, the vehicle is touch-dry, so we can begin the application of the whitewash. Acrylic or water based paints should be used for this. I'm using Tamiya's flat white. I've thinned the paint as I would for normal application (1 part paint to 4 parts thinner). Some areas received a heavier application of the paint just to add some variation.
Fifteen minutes later, armed with a soft brush dampened with warm water, I started brushing over the white. If you find that the paint isn't being removed, just dampen the brush again and keep rubbing it over the area. Eventually the white paint will start to come lose, exposing the base colour beneath. Keep working all the areas until you get the look you are after.
Using the sponge technique, the worn outer edges are treated to re-add some of the chipping.
The vehicle is then treated with an application of a brown filter to give a weathered appearance to the white.
I gave the paintwork a good hour to dry before starting to add some colour variation/mapping to the white paint. This was done using Humbrol off-white applied directly from tin to the model, and then working it in with a brush dampened with thinner. This was done to specific areas only.
Tamiya white enamel was then applied in a dabbing motion around the edges, bolts, hard to get at areas and some of the wider flat surfaces where a brighter white would still be visible. The paint was not thinned or applied with a dampened brush.
The fenders and lower areas of the vehicle were then given a brown oil wash.
At this point we can set the kit aside and continue with the rest of the build and/or painting.
As mentioned earlier, this technique can be used to simulate a rusted vehicle, chipped paint, etc..