How to Paint Lines on Model Tarmac Roads

Basic flat tarmac roads are easy to model for beginners: I just use cheap black fine grain sandpaper. It comes on a roll and is cheap and easy to cut to size.

Here's a tip, though, only mark and cut it from the back. The grainy side, after all, has been designed to smooth rough wood, and tends to do the same on pencil lead and even cutter blades (blunting them both in the process!)

Measuring Up

Depending on how prototypical you want to be, and how much space you have, there are two ways to go about making a tarmac road: measure and scale down, or place and guess. You may even start out by measuring, and then find that there just isn't the space to do what you wanted to do!

For example, for my street scene, I went out into the road to measure the width of the lines, as well as the width of the road, only to find that on a layout measuring 40cm in depth, there wasn't enough space. So, I placed two cars side by side, and that became the lane widths.

Painting Lines on Model Roads

The basic theory is easy enough:

1. Calculate the distance from the pavement;
2. Calculate the line width;
3. Mark up the area to be painted with decorators tape;
4. Paint.

The resulting road should look something like the picture on the right.

Marked Up Tarmac Road

The overlap isn't intended to be the centre line: the road isn't wide enough for that, and so won't be entirely prototypical. However, as mentioned above, due to space restrictions, 'good enough' will have to do! 

The next stage is to choose your paint colour. I use Humbrol 81: Pale Yellow. This looks correct for UK yellow lines.

For white lines (parking spaces, for example), I use a basic matt white paint.

It's important to dry brush the paint onto the sandpaper. Because of the fine grained nature, you will almost never be able to get the decorator's tape to form a perfect seal. If you try, by smoothing it down, you will also usually scrape your finger along the sandpaper at the same time, leaving an unsightly trace.

Failed Yellow Lines

The result of straight painting can be seen on the left.

Paint has bled over the edges, leaving unsightly splodges. So; unless the tape can provide a perfect seal, it is going to be impossible to get that "just painted" look.

Dry brushing the lines has two advantages: firstly, you don't get the bleeding underneath the tape, and secondly, it looks like a realistically aged line, rather than a fresh one.

The technique I use is to load up the brush, and then paint it onto the tape, as if using it as a mixing palette. Once there's no more paint on the brush, I then stipple the paint from the 'palette' onto the sandpaper.

Painted Yellow Lines!

(This doesn't do the brush any good, by the way, but for these tasks, I use cheap bulk-buy packs from a local DIY store.)

The mess that this makes can be seen on the right.

It's also quite wasteful in paint; I'm fairly sure there's a better way (I've toyed with the idea of using a sponge rather than a brush), so feel free to comment below if you have advice from your own painting experiments.

However, I'm quite impressed with the results that I get. Here's the finished product:

Finished Yellow Lines

I've zoomed the photo a bit to show the texture of the sandpaper, as well as the slight blotching of the lines that give them that lived-in look. Whether this would work as well in N or O gauge, I don't know, but for OO/HO it seems to be accurate.

Just for completeness, here's the road placed on the layout:

The image on the left shows the original road, with the one on the right showing the new extension, painted in the step-by-step process above. If things look a little dicey (one of the lamp-posts is a touch slanted) then that's because nothing is stuck down yet!