"Well, paint with it?" would be the most obvious answer, but hold on. We will get to painting eventually. Today, we'll focus on how the airbrush works. And there will be homework.
- Nozzle. The part that is nearest to your work piece and also the one you will care about the most. On the picture the nozzle itself is not visible; it's a very, very tiny funnel in which the needle's point sits. Just behind the nozzle the paint and air mix together, and by retracting the needle the nozzle is opened, allowing the spray to happen. Unscrew the needle guard for a very thin line; this is essential for detail work.
- Air valve. Here the magic begins. By controlling how much air gets into the mixing chamber different effects can be achieved. The rule of thumb is that the thinner the paint, the less air it needs to spray. This also controls the thickness of the line you produce when painting. When undercoating and varnishing (and cleaning) open the valve all the way. When actually painting, tighten the screw as you see fit. This, as with all things, requires practice, but is quite easy to grasp: if your paint spills, you need less air, if the nozzle clogs or paint starts spraying in droplets, you need more.
Be careful with low air amounts: the lower you go, the sooner the nozzle clogs. It's inevitable.
- Trigger. It works in two ways: when depressed, it opens the airflow. No control happens here, it's merely a flow/no flow action. When pulled, the needle is retracted and paint is released into the mixing chamber. Combine both of these and you will have what airbrushes are supposed to do.
This is the most vital part to practice. The amount of paint released is essential. You can control it better with the screw under point 5, but when practicing, unscrew it all the way and control the trigger only with your finger.
- Paint container. Easy as that.
- Needle screw. By tightening or loosening it you control how far the trigger (and hence the needle) can be retracted and how much paint is flowing. Some airbrushes actually have a scale printed here, which is very helpful. As with the air valve, when cleaning, open it all the way. However, when undercoating or varnishing it is tempting to allow more paint to flow - be careful with this. It's all too easy to make a spillage. Two or three thin coats are better than a single thick one - and the airbrush covers wonderfully thinly.
Alright. That's the long and short of it. Now practice.
Get yourself some white foamboard. It goes for dirt cheap at art supplies stores. This will be your practice sheet. Here is mine:
For your very first encounter with the airbrush, don't use paint, just tint some water. See how it behaves, how flows, how it reacts to different pressures and amounts released.
Remember, an airbrush is not a brush! It does not touch your material - distance between them is a factor!
As for the promised homework, do the following:
- doodle, simple as that
- draw a straight line
- draw some parallel lines. Try to be as neat as possible.
- draw a circle, again, as perfect as you can
- draw a spiral
- draw a triangle
- draw a rectangle or square
- draw the thinnest line you can
- fill your triangles and squares with a gradient.
Got it? Great. See me here next week for your reward. Thanks for reading!