This is the first of two articles about the technique of dry-brushing which is one of the oldest and simplest methods used by scale modellers to give models a realistic finish and improved visual appearance. This article gives background information whilst the second article contains a step-by step guide.
Dry-brushing has two purposes. Where the surface of the model is textured, dry-brushing can emphasise this texture. It is particularly good at showing up the casting textures on armoured vehicles or the tread pattern that is often put on horizontal surfaces to improve grip. Dry-brushing is also useful for highlighting the edges of models. On full sized vehicles it is noticable how the edges often look lighter because they reflect the light.
The History of Dry-Brushing
In the 1960s when the introduction of injection molded plastic kits made scale modelling popular, it was by no means certain that models would be painted at all. Manufacturers generally gave painting instructions and model paints were available, but at the same time the colour of plastic used would often be chosen so that painting was not absolutely essential and many modellers took advantage of this.
As standards improved over the years, painting models became almost universal. At first, most models were brush painted, but the introduction of the airbrush allowed modellers to acheive much better results and gradually took over until we reached the position we are at today when amost all serious modellers use an airbrush and painting a model is often given more care and attention than the building of it.
However, no matter how good the paint job is, a model can still appear lifeless, unrealistic and ‘toy like’. Quite simply, light and shadows look different on scale models compared to full size objects, so simply painting a model the same colour as the original will not make it look realistic.
As the decades have passed, modeller’s have sought techniques to add life, interest and realism to models so that today there are a plethora of different methods and each modeller has his or her favorites. Colour modulation, pre-shading, post-shading and pin-washes are but a few of these methods. One of the first to be developed was dry-brushing.
Dry-brushing involves passing a paint brush that has almost no paint over the surface of the model. Only the edges and surface details of the model pick up the paint, so the technique highlights surface texture and makes edges stand out. It is relatively easy to master and being one of the first techniques developed it became almost universally employed. Dry-brushing a model became a standard technique used by almost every modeller on almost every model.
The technique is best employed when it is used with subtlety. Regrettably, it was often used where it did not benefit the model and was often overdone, making some models appear garish. For this reason, when other techniques became available, dry-brushing fell out of favour and became deeply unfashionable. At one time, no modeller would have shown a model in public unless it had been thoroughly dry-brushed, but now almost the opposite is true and some modellers feel they have to apologise and explain themselves if they have used dry-brushing on a model.
This is a shame because dry-brushing is a very useful technique when used in the right place with moderation. The answer is to treat dry-brushing as one of many painting techniques in the modeller’s ‘tool box’ and like any tool it should only be used where appropriate.
I feel that most models still benefit from dry brushing, but often only in selected places and always with care. Dry-brushing should enhance a model without being noticable.
A Explanation Of The Technique
Types of paint
Dry brushing can be done with oil, enamel or acrylic paints. Most modellers prefer oils or enamels (or a combination of both) because they have a longer drying time. However, acrylics can also be made to work by either thinning them well, or by adding a retarder that slows the drying time.
Acrylics are still less forgiving than the other types because when dry they are very difficult to remove whereas enamels and particularly oils can still be removed by using a solvent even if they have become dry to the touch. Therefore, when using acrylics you need to make sure that you are happy with the effect on one part of the model before moving on, because you will be unlikely to come back later to rectify any mistakes. Acrylics have the advantage of being less toxic, non-flammable and they will not stink out your room, so are particularly suitable for younger modellers. The shorter drying time of acrylics can also be an advantage since you can almost immediately move on to the next stage of the model, or you can lay several light layers of acrylics on top of each other without having to wait for each one to dry.
When dry-brushing you will almost always be using a lighter colour than the underlying colours already on your model. There is a choice of either choosing a different colour paint that is a lighter shade, or lightening the same colour paint that has already been used. Both choices require care.
When using a different colour paint of a lighter shade, it must be compatable. You can not use any light green over any dark green, or any light red over any dark red. Unless the colour you are using is one of the primary colours (extremely unlikely since there are millions of colours and only 3 primary colours) it will be a mixture of other colours.
The diagram of a colour wheel on the right shows the relationship of colours to each other. As you can see, the colour green is more than just light green or dark green. It can lean towards yellow or blue. When choosing a lighter colour paint it is normally best to choose a colour with a similar tone e.g. if your base colour is a yellowy-green then you need to highlight with a lighter yellowy-green. This can only be done by eye.
Rather than choosing a different colour to the base colour you can try to lighten the base colour. The first instinct is often to add some white paint and this can be a mistake. Take another look at the diagram of the colour wheel. Do you see white on it? White is not a colour but a mixture of all the other colours, so by adding white to your base colour you are in effect adding a little of every colour of the rainbow. Adding a little white will work to lighten the colour, but if you add much more than 10% white to any colour the tendency is to end up with a washed-out tone.
|HINT: Just as you should avoid lightening paint by adding white, the same applies to black. Adding black will make any colour appear dull so try to use another paint with a darker shade.|
To lighten a colour it is much better to add another brighter colour. To lighten a dark blue try adding a sky blue. For example, when drybrushing over Tamiya Desert Yellow, I might start with a mix of Desert Yellow and Buff with a 50/50 ratio. The effect initially will be very subtle – almost unnoticable, but on subesquent passes I might add more buff and then finish off with a few drops of bright yellow or white.
You will probably find a largish brush will work best. Dry-brushing is hard on brushes so it is best to use an older brush. It is important to have some spring in the bristles so do not be tempted to use a cheap brush because the results will be disappointing. Some people prefer standard round brushes and others prefer flat brushes, so try both to find out what suits you.
Mix up your desired paint. I find that making it a little thinner consistency than would be used for normal brush painting works best. Dip the end of your brush in the paint and make sure all the bristles are well soaked at the end then try to remove as much paint as possible. Transfer the brush to a paper towel and gently wipe the brush on the towel until it leaves almost no mark. Then lightly draw the brush back and forth over the high spots of the model. You willl need to brush back and forth many times as the best effect is acheived with slow gradual build up of paint. The direction of brushing is very important and should be perpendicular to any edges or raised detail.
One of the biggest mistakes is to overdo the dry-brushing and this often comes from leaving too much paint on the brush. It is a good idea to test the brush on an old model, or some other object with edges e.g. a card or plastic box before you apply it to the model.
Dry-brushing works best when done in several stages. Each stage should be lighter than the previous one, the brush should be applied with a lighter touch and the area covered should be less.
When you have been dry-brushing for a while you may find your paper towel has become quite damp with paint and at that stage you may no longer need to recharge the brush from the palette but simply wipe it on the paint soaked paper towel to pick up enough paint. Remember that with dry-brushing the actual amount of paint that is put on the model is minimal.
It may take some time to completely dry-brush a model, so beware of paint beginning to dry on the brush. You may have to stop and wash the brush and then start again.