Two basic techniques – blocking in and washes
It may seem a bit boring, but probably the best thing you can do to start with is to thoroughly paint the underframes of your wagons. It’s the start of a process which could be described as ‘differential painting’ – in a broad and simple way, a form of texturing that will make your models look like they are actually made up of sheets of plywood, steel sections or whatever, instead of a lump of injection moulded plastic.
Painting the underframe of any RTR wagon is a simple process, and will immediately lift it beyond looking like a toy; whilst steel framed wagons certainly had black underframes when freshly outshopped, the average black plastic moulding still looks pretty much like black plastic, and a coat of suitably matt paint will overcome this. One thing I sometimes see is a partial covering of the chassis – this to me doesn’t cut it, as it still leaves some of that unrealistic ‘plastickness’.
Anything tending towards a brownish shade will convey an impression of rust and road dust – this High Goods has been blocked in with nothing more than a mix of matt black and Revell 84 Leather, applied neat:
The wagon below is wooden framed and has been treated with Humbrol 98 Chocolate, which is a greyer shade more suited to portraying worn but dusty timber. It was then worked over with a thin wash of brown to add tonal variation to some of the parts that would be metal on the real wagon:
Don’t forget to do the wheels as well (front and back) – both of these wagons have standard Bachmann wheels but the painting has given them a more subdued ‘finescale’ appearance.
Moving onto the bodywork but picking up on that last caption, a ‘wash’ is a very versatile procedure. In its simplest form it’s just an application of paint mixed with thinners, in whatever proportion seems appropriate. So at this stage we are moving on, into weathering ‘proper’ where the aim is to not totally obscure the base finish, rather than using the paint ‘full fat’ to acheive complete coverage.
A thin wash will obviously have less effect than a thick one, but a medium thickness one which is then redistributed and partially removed is probably the most effective for what will follow. Experimentation is the key, in order to get the feel of how different paints behave on different surfaces, and an overambitious application can usually be pulled back with another application of thinners onto the model, even if it’s begun to dry.
The pictures below show quite heavy applications, mostly to get the point across but for someone who’s just starting, I’d recommend a thinner wash until you get the feel of things. Even then, it’s generally best to work in small areas at a time with small amounts of paint:
Washes can be worked with the brush or (as seen here) largely removed with a cotton bud, which will leave a residue of paint in precisely the places where dirt would gather on the real wagon:
At the other extreme, ‘drybrushing’ is a procedure where a very small amount of paint is loaded on the brush, then mostly removed, on a rag or such. The residue is then flicked over the model to produce highlights (usually over raised detail or texture, but it can be of use on flatter panels). There’s no picture of this because it’s done in seconds, it’s actually quicker to try it than to explain it. Drybrushing is in my opinion a fairly limited technique in rolling stock applications, but it’s worth trying to form a frame of reference because between the two basic techniques lie a whole range of nuances, which you’ll naturally get a feel for as you progress. Wrist action is important; whereas painting a complete model calls for smooth, even brushstrokes, anyone who’s done any domestic decorating will be familiar with the different technique used for instance to get into the skirtings in a corner, or to paint a door edge. I tend to drift into using terms like scrubbing, smearing and stippling for variations on these themes; apart from being reasonably self-explanatory anyway, they are again something easier demonstrated than described.