Brushes Shapes & Hair

From  handprint.com 
Specific shapes of paint brushes have been developed over the years in an attempt to assist the artist in his/her work. It would be difficult to say which shape is the most popular, but near the top would have to be "flats." These brushes have neat square edges, pointed tips, and moderately long hairs. They charge well with paint and deliver strokes that vary from fine to broad, depending on pressure and angle of application.

Flat. Sometimes called a one stroke, these are chisel-shaped brushes with a straight edge that can smoothly release a very long stroke of paint, used for laying down large areas of even color or water, precise color edges, graded washes, and a variety of shapes less convenient to render with a round. Nearly all the strokes made with a flat have an angular or straight edge to them, so they are often used wet in wet (which disguises these characteristic brush marks) or boldly in "angular" painting styles. Sizes are usually measured in inches along the flat edge, and typically include 1/8", 1/4", 3/8", 1/2", 3/4" and 1".

Mop. Rounds made with very fine, soft hairs (usually squirrel hair) that can hold a large quantity of water when wet or can wick up a large quantity of water when thirsty. Good mops come to a precise point and can be used for very controlled applications of color or water from thin lines to sky wide washes. These soft hairs limit the range of brush marks in comparison to a round, but this coarser, "out of focus" effect makes them ideal for backgrounds and large color masses. Sizes run from #0 to #14.

Wash. Looking like miniature house painting brushes, wash brushes extend the range of flats to much larger widths, hold much more water, and release it over a wider area. Sizes typically include 1", 1-1/2", 2", 3" and sometimes 4", depending on manufacturer and type of bristles used.

Most paintings will require two or more of these basic brushes. In addition, there are a number of specialty brushes that are less frequently needed because they are designed to serve limited purposes, usually some kind of specific texturing effect which the basic brushes handle less effectively:

Bright. Flats with shorter (and usually stiffer) hairs -- usually about as long as the brush is wide. They hold less paint than regular flats, but can be used more assertively in lifting, splattering, scumbling, and similar texturing techniques. Sized as flats.

Acrylic. Flats with synthetic fiber bristles and a clear plastic handle that ends in a beveled edge, useful for burnishing, rubbing or scraping the watercolor paper. Sized as flats.

Filbert. Oval flats that come to a point when wet, usually made with soft bristles such as squirrel hair, and used for graded washes where the width of the wash strokes must be varied, or the wash is laced through detailed brushwork requiring a point. Sized as rounds.

Rigger. Brushes with very long, thin hairs, originally used to paint the rigging lines in nautical paintings, but great for any rendering of fine long lines. The long tip of a good rigger will hold a fair amount of paint and will disguise minor wobbling in the hand through the spring of the tuft. Sized as rounds.

Liner. Basically a rigger wrapped in a round. The hairs often do not come to a needle point, so that the line rendered can be made thicker, while the length of the liner tuft allows the line to keep a more consistent width than the line possible with a round. The belly hairs hold a large charge of paint, which lets you paint a rather long line for its width. Sized as rounds.

Detail. A stubby round tapering quickly to a precise point, used for painting signatures, short lines that vary in width, stippling, hatching, rendering single leaves, and similar effects. Sized as rounds.

Fan. As the name indicates, brushes with a fan shape used for drawing grass  or twig  clusters of parallel lines and for softly adjusting washes. Sized as rounds.

Travel brush. Collapsible round or mop brushes that encloses the tuft in the handle for protection during travel. Only useful for quick sketching with a pocket pan set and a small block of watercolor paper. The largest sizes can be used for washes, and travel mops are also available from Isabey. Sized as rounds.  

Japanese Sumi brushes. These come in many styles and sizes. The gyokuran or koraku are basically calligraphic tools: they deliver elegant flowing strokes that characteristically change texture as the fluid in the brush is exhausted, from the wet beginning of the stroke to the dry finish. This is partly because the brushes have a poor carrying capacity, and release liquid fairly quickly; and also because the goat hair tufts are coarse and soft. For the traditional Japanese calligraphy, which develops a skill in handling the old kanji ideograms as artistic icons, this variation in texture has a lovely expressive effect. In most other painting situations, it can be a nuisance. Sized in inches.

The flat hake brushes are used dry (without any water or paint in them) to gently stroke and coax the distribution of paint or water in wash areas after the wash solution has been applied with another (wash) brush. Some are designed as individual tufts set in a row of bamboo stalks; others are made as a single row of hairs set in a thin, flat wooden handle. They are quite limp when wet, and shed hairs relentlessly, which makes them nearly worthless as direct painting tools; when the hairs are wet they also straggle across a wash, leaving unsightly marks. Sized in inches.

Nearly all the magic in a brush is in the selection of the tuft materials and how they are shaped and secured to the handle. This determines the resiliency or "spring" in the brush, how much water it can hold, the variety of effects it can render, and how long it stands up to use. 

Brush Hair

The most exalted hair for use in watercolor brushes is kolinsky sable, made from the winter pelts of the Siberian kolinsky, Mustela siberica, a variety of weasel or mink (shown at left, wondering why you are so interested in his tail). Considered the ideal hair for watercolor brushes, kolinsky sable is durable and holds a lot of water; at its best, it has a spring and resilience unmatched in any other brush material.

In the brush maker's world, the strict definition of "kolinsky" refers to hair from the tail of the winter pelt of a male animal; this hair is a distinctive orange brown with a dark tip. The animals must live in extremely cold climates for the hair to achieve the desired thickness and length; kolinskies do not breed in captivity, so the animals must be caught in the wild by vodka fortified trappers.

Less desirable grades of hair also called "kolinsky" come from the back or flanks of the pelt, from female animals, and from summer coats; this hair is sometimes very different from the winter male tail. The point is simply that the kolinsky does not have a year round consistent crop of hair, as your cat or you do (with or without Rogaine); so the label "kolinsky" cannot refer to a specific set of hair attributes.

But it gets worse. Some "kolinsky" brushes are actually made from the pelt of related species of sable or mink, usually grown in captivity in somewhat warmer climates. These are more accurately described as types of red sable, but are marketed as "kolinsky" all the same. Conclusion: the label "kolinsky" as applied to currently available watercolor brushes does not mean any consistent type of hair or hair attribute. The right attitude is always to replace the word "kolinsky" with the word "varmit," and proceed to evaluate the brush from there.

The special merit of a kolinsky hair is that it gently tapers at both ends, with a very sharp point at the tip and a widening of the shaft (the belly) about two thirds of the hair's length from the tip to the root. The taper of the hair from the belly to the tip is what allows kolinsky brushes to point so well.

All kolinsky brushes are expensive, sometimes exorbitantly so. There is heavy marketing emphasis on kolinsky hair brushes, which is ironic since many experienced artists feel that the quality of kolinsky and sable hair has declined significantly over the past few decades. And this marketing pressure distorts the integrity of the final products.

There are many steps from harvesting the hair to tying off the tuft of a brush -- the wholesaler sells a range of qualities, and the hairs purchased from the brush manufacturer must be further inspected and sorted, and some manufacturers are more rigorous than others about discarding broken, short or falsely labeled hairs from their stock. The supplies available to wholesalers vary because of many business and environmental factors; some wholesalers are better than others about informing their clients of these variations.

In short, without manufacturer or import regulations, and given the fundamental variation in the seasonal pelts of these sexually dimorphic mammals, the mere label "kolinsky" tells you nothing about the quality of the brush you are buying, and as often or not is misleading as to one or more qualities of the hair actually used. If you can visit a well stocked art retail store, compare the brushes from different manufacturers and see for yourself! 

Test Them: Here's a way to test them, Pick out a few medium size brushes comb out the glue holding the hairs together, and soak them in some water for a few minutes. Stroke them against some watercolor paper until they form proper points. Take each brush separately and hold it perpendicular to the paper surface, then lightly press down on the brush until the point bends. Lift the brush. Those made of male hair will snap back straight, while others hairs ( red sable or mostly female kolinsky) will remain slightly bent.

Red sable. This is usually hair from the marten or sable Mustela martes or Mustela zibellina, slightly thinner and stiffer than kolinsky but comparably resilient and thirsty. Red sable is usually a somewhat darker and duller brown than kolinsky, and the tips are a little blunter because the hair has a more abrupt taper. Because red sable hair is not as long as kolinsky, there usually is less hair visible outside the ferrule in a red sable brush (the ferrule must pinch the hair just below the belly to get the tapering effect). Sable can make excellent brushes when the hairs are high quality and are arranged properly by the brush maker. In many brush brands, "sable" hair is almost indistinguishable from the "kolinsky" hair.

Squirrel hair. A dark, soft, dense hair that is normally used in brushes that must hold a lot of water or that do not need spring in the tip (for example mops, flats, filberts, wash brushes). Squirrel is an exceptionally soft, absorbent hair. All varieties produce a brush that is very absorbent, not springy, but that comes to an excellent point. Kazan squirrel hair is brown, thin and quite soft, sometimes with a salt-and-pepper speckling of white. Canadian squirrel is a slightly thicker, less resilient, considerably shorter hair with more belly; it is usually a variegated yellow and black.

Ox hair. Usually a brown or reddish hair, long yet stiff, taken from the ears of cattle. It will not come to a point because the hair is roughly cylindrical throughout its length. It is inexpensive, strong and springy, which makes it great for rougher brush techniques. It is also often mixed with other less resilient materials (such as inexpensive sable or synthetic fibers) to give the ox hair tuft a better pointing capability. Sabeline is very fine ox hair, dyed red to match the color of red sable, and either used by itself or with sable (or nylon fibers) in blends.

Boar bristle. A pale or white bristle, very stiff, taken from the ears of hogs. "Bristle" means that the shaft does not come to a single point but frays or splits near the tip into "flags" or small protrusions. These tend to reduce the capillary action, making bristles more suitable for oil or acrylic brushes. Watercolorists sometimes choose them in brights or fans for textural effects, or in brushes used for scumbling or scrubbing away (lifting) paint layers or painting mistakes.

Mongoose hair. Another hair more commonly used in acrylic or oil brushes. Has a very distinctive and delightful coloring: brown tipped, white banded, then dappled white and black along the shaft. Holds a lot of liquid, and is stiff but with velvety tips. Some watercolorists use these brushes for textured washes and a variety of scumbling effects.

Goat hair. A long, coarse, wavy and limp hair that is most often found in Japanese wash and calligraphic brushes. Because the shaft is very soft, wavy and cylindrical (does not taper to a point), it is not suitable in traditional rounds that require a needle point.

Camel. The most appropriate translation for this label is "an inexpensive brush not made from a camel." The hair is not from a camel, is too inexpensive to label accurately, and may be many other types of hair besides sable (typically the hair is black squirrel, or a blend of two natural hairs such as squirrel and ox).

Synthetics. The variety of synthetic fibers on the market is large and growing. The best synthetics are as resilient as sable and as thirsty as squirrel, though they soften and wear quickly in use. Tapered synthetic fibers retain their shape better than "level filament" (untapered) fibers. They are used in the same shapes as other brushes: flats, brights, filberts, and rounds. Synthetic fibers are made of nylon, polyester, or other filaments. Color is not a factor in judging their quality.

The best synthetic fibers are extruded and treated in different configurations to resemble natural hair. Increasingly sophisticated extrusions are making it possible to produce much less expensive brushes with many of the same qualities as natural hair. Synthetic brushes also combine filaments of different diameters to achieve various qualities. Brush fibers are mostly of Japanese manufacture, though they are also made in the USA and Europe.

Synthetics generally don't point very well when used alone in rounds, so they are often mixed with natural hair. Many lines of brushes available today mix bristle types, for example natural sable with synthetic fibers, or ox hair with red sable (these are called blends). These mixed bristle brushes are often bargains and produce perfectly satisfactory results. Many artists purchase synthetics by the dozens because they are so inexpensive, and throw them away as soon as the brush begin to wear or fatigue.