Know your airbrush

Painting with an airbrush can completely change your scale modeling and open new finishing possibilities. But you should know the basics before you decide on the kind of airbrush you want to use. Let’s dive in!

What is an airbrush? 

In simple terms, an airbrush compresses air and pushes it through a narrow nozzle where it atomizes paint and blows it out in a controllable pattern, 1. Think about it as a miniaturized, precision version of the paint sprayers used for houses and cars. Airbrushes are used in many professions and hobbies, and they are the perfect tool for applying paint to scale models.

Single- versus double-action 

Airbrush designs differ, but they can be divided into two basic categories: single-action and double-action. Airbrush types can affect the way paint is applied, ease of use, and clean up. 

In a single-action brush, the trigger controls only air flow, and it’s usually either on or off, 2. Paint flow is set by adjusting either the nozzle or the needle. This makes them easy to use, especially for beginners, because there’s only one thing to consider while spraying and a lot less chance of applying too much paint. On the other hand, single-action brushes tend to be less versatile because adjusting the paint flow is generally done while the brush is not in use.

On a double-action airbrush, the trigger controls air flow and paint volume, 3. Generally, the air pressure is controlled by depressing the trigger. Pulling back on the trigger moves the needle within the nozzle, which allows more paint through and results in a wider pattern. Skilled painters can manipulate double-action brushes to easily create interesting effects. But the versatility of double-action brushes makes them harder to use as there are more variables to master.

External versus internal mix 

An airbrush can mix paint and air in two ways, either externally or internally. External brushes are usually less expensive than internal brushes, but they tend to produce a wider, harder-to-control spray pattern. Internal mix brushes are often easier to use and control, but there are many builders who achieve terrific results with external-mix brushes.


Bottles, color cups, and gravity feed

Airbrushes hold paint either in a bottle that attaches to the brush, usually from underneath, or in an open-top color cup. Bottles hold more paint and can be closed — a handy way to prevent unfortunate spills or splashes. Most color cups mount on top of the brush. They hold less paint, but because gravity helps move paint into the body of the brush as opposed to air pressure in a bottle-fed brush, you don’t have to use as high a pressure to spray. That means you can achieve subtle effects more easily.

Armed with this knowledge, you can better research airbrushes and decide which one is best for you.

Want to learn more about airbrushing and scale modeling? Get the scale-modeler’s how-to guide, Essential Skills for Scale Modelers.