Most paint problems on RC bodies come down to one thing: the wrong paint for the plastic. There are two kinds of body and each has its own paint. Get that match right and everything else is technique.
First, which plastic is your body?
| Polycarbonate (Lexan) | Hard plastic (ABS or styrene) | |
|---|---|---|
| Looks like | Thin, clear, flexible. Springs back when squeezed. | Rigid and usually moulded in a colour, like a plastic model kit. |
| Found on | Almost every buggy, truck, touring, drift and rally shell. | Scale crawler and truck bodies, some tank and lorry kits. |
| Painted | On the inside. | On the outside, over primer. |
| Paint to use | Polycarbonate paint only. | Ordinary model primer and paint. |
The rest of this guide is about polycarbonate, because that is what nearly every clear shell is.
Why polycarbonate needs its own paint
A polycarbonate shell flexes every time the car lands, rolls or clips a barrier. Ordinary enamel, acrylic and car aerosols dry to a hard skin that sits on the surface, so the first good flex cracks the skin and it comes off in flakes. Polycarbonate paint is made to bite into the plastic and to stay flexible once dry, so it moves with the shell.
That is also why you should not use polycarbonate paint on a hard plastic body: its solvents are stronger than a styrene kit needs and can mark the surface.
Spray cans or airbrush
| Spray cans | Airbrush | |
|---|---|---|
| Best for | One to three solid colours, stripes, simple two-tone designs. | Fades, fine detail, custom mixes, many colours on one shell. |
| You need | The cans and some masking tape. | An airbrush, a compressor, paint and reducer. |
| Cost to start | A few pounds a can. | Higher, but paint per shell is cheaper once you have the kit. |
| Learning curve | Low. Thin coats and patience. | Steeper. Thinning and pressure take practice. |
Start with spray cans. A good many club racers never use anything else. If you want fades and fine work, move on to airbrush paint and read Airbrushing an RC body.
The finishes, and what each one needs behind it
| Finish | What it does | Back it with |
|---|---|---|
| Solid colours | Opaque after three or four coats. The easy place to start. | White for brightness, or straight to black. |
| Fluorescent | Very bright but thin; looks washed out alone. | White, always. |
| Metallic and pearl | Fine flake that catches the light. | Silver to keep it bright, black to deepen it. |
| Candy and translucent | A tinted clear. The colour comes from what is behind it. | Silver or a metallic for a deep, wet look. |
| Chrome | A mirror effect when applied in very light coats. | Black. |
| Window tint (smoke) | A see-through grey for windows, sprayed after the window masks come off. | Nothing. |
| Matt varnish | Sprayed on the outside to knock the gloss back, for scale and military finishes. | Nothing. |
How much paint to buy
- 1:10 touring, drift, rally or buggy shell: one 150ml can of the main colour, one of white or silver, one of black.
- 1:10 short course, monster truck and 1:8 shells: two cans of the main colour. A 400ml can of white or black is better value for backing large shells.
- 1:18 to 1:28 shells: one can does several.
- Each extra colour in a design: one can is plenty; most of the can will be left for the next shell.
Different makers use different solvents. Most combinations are fine, but if you mix brands, let each colour dry fully before the next and test on an offcut from the shell first.
Storing cans
After spraying, turn the can upside down and spray until only gas comes out. That clears the nozzle so it works next time. Store cans indoors: paint that has sat in a cold garage sprays badly until it has warmed through.
Ready to spray? Go to How to paint an RC car body.