Painting rust the easy way
Chances are anything ferrous in the wastelands of Nuclear Renaissance (or anywhere else for that matter) is going to be rusty! The following guide will give an insight into how I like to paint rust, particularly on vehicles.
The vast majority of painters I've seen tend to paint an area in its intended base colour and then apply metal chips and rust on top. Bobbins, says I! Granted this makes sense if you just want a few miniscule chips out of an otherwise production-line pristine paint job, but if you want more advanced oxidisation this method doesn't produce a natural look. After all, paint chips off of rusted metal, not vice versa.
The metallic base coat
First things first you need to render your metal object ‘metallic’. For this I invariably use the age old method of base coating black and then dry-brushing with dull metallic silver. Some folk aren’t a fan of dry brushing, and prefer to apply layers of washes and manual highlights. Whatever floats your dirigible, but I think dry-brushing provides a more realistic result, if not as striking. It is entirely a question of taste.
Whatever your chosen method I’d normally recommend giving a few light washes of black or very dark brown over the finished article to prevent it being too shiny (we are going for a neglected item here) and to cover any recessed areas that may have mistakenly picked up a highlight.
When applying washes I think of it as a gospel law that though shall not use inks. They are swiving awful as a rule and tend to result in a glossy mess. Watered down paint is par more effective and economical. Experimenting with the amount of water also allows you to control how subtle your washes will be. As a general rule of thumb I go for roughly 3 parts water to 1 part paint, depending on the colour, applying more water for darker colours.