Modern technology has made some big improvements in watercolour brushes. While there will always be those who swear by the traditional and clamour for Sable, the rest of us have learned that imitation fibres such as Taklon and Golden Sable work just fine, have more spring and ‘snap’ to the bristles (which leads to greater control) and what’s more if you dwell in any tropical areas of Australia you will find your precious brushes of no interest to the local insect life. (Unlike Sable, which on all evidence must taste delicious to silverfish and other studio scurriers)?
Watercolour brushes are commonly termed Rounds or Flats, and then there are Liners and Mops and Filberts. You don’t need a lot of brushes in Watercolour; you just need the right ones for the job. Rounds are the classic watercolour brush shape – a soft bulbous base which tapers to a fine, flexible point. Flats are a straight edged brush which are indispensable for laying down large, even washes fast. Liners ( or Riggers) are like a round only long and thin – very useful for endless fine details like grass or hair because they make a fine line and hold a lot of paint Mops and Filberts are a little more specialised, and you can also sometimes find brushes made for sign writing and lettering useful for some tasks. Watercolour brushes differ from brushes made for Oil and Acrylic in that they are made from softer and more flexible material to allow fluid control and expression.
For a good basic start -buy one each of rounds such as no:12, no: 6 and no:2, a decent 1” flat and don’t forget a Liner ( or Rigger) . Practice brush strokes on scraps of watercolour paper, or even the back of discarded paintings.
For large areas always use a large brush.
If you choose a brush that is too small to cover the area with speed – by the time you get to the end of the large area you are covering ,the wash has already started to dry and edges occur which can’t be blended.
For flat, gradated washes use a large flat brush not a round. For soft, expressive strokes rounds are best but it’s not an inflexible rule. Get to know your brushes; they are the expression of your feelings on the paper. Practise on scraps of watercolour paper or the back of abandoned paintings and learn what each of your brushes is capable of.
A Round watercolour brush should come to a flexible point and have good fluid carrying capacity in the base or’ belly’. Don’t buy rounds that will not shape to a proper point. Flats should be even along their edges and mops should be full and soft. Chinese style watercolour brushes can be very expensive and not very easy to use, western style brushes can easily substitute for them.
Always rinse your brushes in clean, cold water. Flick or wipe dry and reshape the points on rounds and the edges on flats. Leave to dry standing up and don’t put them away until they are dry. A good brush should not be damaged by drying standing up but it will get damaged rolling around wet in your painting box and drying with the bristles wedged up against something else. Once a brush has bent or lost its point or become frayed it becomes much specialised in its use – i.e: it will only make one kind of mark on your paper in contrast to being flexible and versatile. This applies to both natural and synthetic brushes.
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