Guide written by:
Jeremy, construction site supervisor, Cardiff
Let your artistic talent flow on canvas, skin, furniture or any other surface - the pneumatic airbrush is the perfect thing! Whether you're a beginner or an experienced painter, the most important thing is to equip yourself well. Let us help you brush up on what's available before you buy!
- Single action
- Dual action
How does an airbrush work?
An airbrush is similar to a paint gun; it projects paint on a surface by means of compressed air. Its key advantage is that it lets you spray very precisely onto any type of surface - canvas, skin, wall, fabric, models, or even pastry, clothing, etc. Connected to a pneumatic compressor, it makes its mark with paint stored in a reservoir. What's great about this tool is that, once you start to master it, you'll be able to draw fine lines, create gradients and block-colour large areas!
There are two main types of airbrush, distinguished by their mode of propulsion.
Gravity airbrushes have the reservoir fixed above the body of the tool, supplying the paint under the action of gravity. Handy and durable, they can be used by both right and left-handers. This type of airbrush also has the advantage of being compatible with thicker paints. However, it isn't advisable for painting large surfaces.
Suction airbrushes have the reservoir on the side of the body (usually right-hand side) for small-volume models - below the body for large-volume - and the paint is propelled by pressurized air (via the Venturi effect). Removable reservoirs of various sizes can be attached depending on the task in hand. This type of airbrush is a bit more delicate to master because it requires thorough preparation of the paint before use. For left-handers, it's crucial that you choose an airbrush with the reservoir on the left so it stays out of your way.
What are the different types of airbrush?
Two major families of airbrush are to be distinguished as follows.
Single action airbrush
The single action airbrush is ideal for beginners. This type of brush lets you control the air flow with a trigger. Easy to handle, use and maintain, it's suitable for new or occasional users. It also lends itself well to block-painting large surfaces. It's suitable for craft applications and applying high viscosity paints and ceramic glazes.
Dual action airbrush
The dual action airbrush is a real artist's tool! It lets you control both air flow and the flow of paint, allowing you to produce more complex effects, gradients and very fine lines - less than a millimetre wide! Its use requires a little experience and practice, but once mastered it can produce a huge range of effects, line types and opacities. It's also more comfortable to hold - an important factor when painting for hours on end. However, it's not suitable for painting large surfaces, and regular, meticulous maintenance is required.
What else do I need to know before I get started?
Just one or two little things, hold on! Owning an airbrush is all very well; actually being able to use it is a step up!
The compressor is an essential piece of kit - without compressed air your airbrush won't be any use at all. A quick tip - a compressor without a storage tank will do the trick. It's inexpensive because of its simple design, and provides the essential compressed air your brush needs. On the other hand, it has to run continuously during your painting session since it can't store any air. Once you've mastered your technique and you're using your airbrush more intensively, go up to a compressor with storage tank. A 1-25L tank is perfect and allows you to paint for quite a while before the motor kicks in to refill it. One of the main advantages of having a tank on your compressor is that you can control the pressure of the air delivered. However, it does make your compressor bulkier, noisier and more expensive and requires special maintenance (though nothing too complex). In any case, choose a compressor equipped with a filter to avoid condensation forming in the tank, especially if the ambient air is humid.
Nozzles / needles
The ideal is to have a range of nozzles and needlesso you can just as easily produce fine lines as broad swathes of colour. A set ranging from 0.2 to 0.5mm is perfect to start off with, smaller diameters corresponding to finer lines. A fine set and a medium set give the best compromise between fine definition and broad coverage. The nozzles and needles are very fragile, so make sure you have spares to hand because it's easy to twist or damage them - through dropping the brush, disassembly for cleaning, etc. Make sure to choose a model of airbrush with easily available spare nozzles and needles, and check the price beforehand as you'll need to replace them frequently.
Reservoir and paints
Depending on what you plan to do with your airbrush, the reservoir volume is an important element because it dictates how much paint you'll be able to use before you have to refill. For precision work, a reservoir between 2 and 10cc (cubic centimetres) will be sufficient. For larger areas, a minimum of 15cc is required to avoid excessive refilling. There are several types of paint you can use with an airbrush: acrylic, oil-based, nitrocellulose, etc. To start off with, go for water-soluble acrylics: they're easier to prepare and much cheaper than more specialized paints. Reservoirs can be made of steel or glass - the latter generally being higher capacity. Think about location and weight: a centre-mounted reservoir can be more comfortable to use than one on the side in terms of balance.
Range of nozzles and needles
The various types of airbrush nozzles
As you might have guessed, airbrushing is a bit more fine-grain than finger painting! Nozzles differ by tenths or even hundredths of a millimetre. The thickness of the paint jet produced is relative to the nozzle diameter. Close-up on nozzles!
0.15mm: difficult to use as sensitive to small particles. Very precise and as a result must be cleaned frequently!
0.20: requires a little less cleaning; produces slightly thicker lines.
0.30 and 0.40: a little wider still, easier to use when you're starting out. 0.40 is a good starting nozzle which still lets you draw relatively fine lines.
0.50: ideal starter nozzle; requires less cleaning as it blocks less easily.
What's the difference between internal and external mixing?
So an airbrush propels paint onto the target surface by means of... Air! Similar to the fuel and air in a car engine, these two substances must be mixed together beforehand.
Internal mixing: takes place inside the nozzle. The process causes atomization of the paint, giving a fine mixture in the resulting jet.
External mixing: the air / paint mixture is produced outside the nozzle, resulting in a slightly coarser mixture.
For those who don't remember their high school physics, atomization is the outcome of mixing a liquid with air. The atomizer on a perfume bottle is an obvious example: it mixes liquid and air and propels the liquid, in this case the perfume, onto your skin via the pressure of your index finger. An airbrush is a little more complicated in design but the principle remains the same!
Any final words of advice?
True airbrush technique requires skill, precision and practice - to produce results worthy of that title. You'll find at first that blots and blockages are frequent. Poor paint preparation, incorrect operating pressure and inadequate cleaning will all contribute... Don't despair, it's worth persevering!
As regards cleaning, it's a necessary evil I'm afraid. Your airbrush should be thoroughly cleaned after each use. Use a minimum of two full reservoirs to clean out the mechanism (choice of detergent depending on the paint type), before disassembling the needle and nozzle - be careful, they can easily get slippery!
Cleaning is finished off with a brush. Bear in mind that some cleaning products can damage the joints of your airbrush - for this reason, don't use undiluted acetone-based products.
In terms of brand, it's really up to you to shop around. However, do look at the availability and price of spare nozzles! Also, don't forget to protect your airways! A protective mask is absolutely essential. And if you want to avoid getting paint on your clothes, why not wear overalls.
Top tip: if you want to create a mini painter's workshop, like a scale model of a proper paint booth, a cardboard box opened up on one side does a great job of protecting the surroundings.
Weapons at the ready... And remember to keep an eye on the viscosity of your paints!
Read more about painting
To find out more about painting, follow our editors' advice and check out their other guides:
- How to choose your stepladder
Guide written by:
Jeremy, construction site supervisor, Cardiff, 131 guides
Electrician by trade, I first worked in industrial estates where I installed, wired and fixed a large number of electrical installations. After this, I managed a team of electricians for this type of work. 10 years or so ago, I turned to building and construction. From the modest family home, to gyms and theatres; I have been able to coordinate, audit and organise all sorts of construction sites. for 4 years now, I am restaoring and bulding an extrension to a bungalow in the heart of the welsh countyside. My experience in manual work and my knowledge means I am proud to be of service. Terraces, interior design, roofing, plumbing, electricty, anything goes! We have, my wife, daughter and I, built almost everything we have from scratch! So to answer all of your questions, and to orientate and advise you on coosing your tools? Easy!