Brush construction is an intricate and impressive process that seemingly defies our age of technology. The brush heads of natural brushes are still shaped by hand and the tips of the brushes are the natural tips of the hairs on the animal. Any cutting and shaping that is done to the brush hair takes place on the side of the hair that is bound within the ferrule. Most brushes have three parts: a tuft of natural or synthetic hairs, a ferrule and a handle. The hairs are arranged and then cemented into the ferrule. The best brushes have ferrules that are seamless to keep solvents from leaking inside.
Although certain brushes are recommended for specific types of media, brush selection should be based on personal choice. Long handle brushes are generally good for oil and acrylic painting and short handle brushes for watercolor–this is based on the painter’s work distance. Because acrylics dry quickly, they can damage the hairs on a natural brush more easily than a synthetic. Therefore, synthetic brushes can be recommended for acrylics. Bristle brushes are often recommended for the beginning oil painter because they’re economical and hold a good deal of paint. Natural soft hair brushes absorb water well and are good for watercolors.
Brushes are numbered in size ranging from multiple zero (which contain very little hair) to double digits (containing small fistfuls.) There’s no mystery about flat brushes–the size given refers to the distance across the flat of the ferrule where the hairs emerge. Choosing rounds is more confusing, as numbering systems differ by manufacturer, but all generally have the size printed on the handle. When getting started, it’s best to pick out brushes that look like the right size for your work and forget about their numbers.
It’s vital to the life of your brushes to care for them as their value warrants. Never rest brushes on their hairs. Always leave them flat or with the hairs upright. Keep brushes clean during the painting session and give them a thorough cleaning after the session. For water-based paints, switch back and forth between rinsing out with tap water and mildly soaped water. For oil and alkyd paints, use mineral spirits or turpentine in the same manner and finish up with mild soap or brush cleaner and water. Always reshape the brush when work is complete.
Here’s a tip for cleaning really big brushes often used in oil painting. Place an old wire colander in a gallon plastic ice cream bucket. Next, place both in a taller bucket with a lid. Fill the gallon bucket with paint thinner to cover the bristles. Swirl the brushes against the colander and then wipe off the excess with a rag. The big bucket catches any splashes.
Remember that solvents are toxic and should be disposed of as hazardous wastes.
Brushes are possibly the most important investment an artist can make, because the quality of the brush used has almost as much power to damage or beautify a work as the orchestrating artist. When making an initial investment in brushes it’s wise to choose a set. Having a number of different sizes and shapes of brushes provides the artist with as many options as possible to create the vision within his/her mind’s eye.