Since prehistoric times, humans have used brush-like instruments to paint on cave walls. They most likely used sticks with the ends crushed to soften the fibers, and/or animal hair tied at the end of sticks. Until recent history, watercolor brushes were handmade by attaching animal hair to the end of wooden handles.
In the 1800s during the Industrial Age and the invention of the metal ferrule, the manufacturing of watercolor color brushes began. Today, most watercolor brushes are machine-made. Top-quality watercolor brushes are still handmade.
How Watercolor Brushes Are Made Today
Modern watercolor brush making combines traditional craftsmanship with industrial processes. While mass-produced brushes are assembled by machines, premium brushes still rely on skilled artisans for shaping and finishing. The quality of a watercolor brush depends largely on how its hair or fibers are prepared, shaped, and secured.
Preparing Natural Hair for Watercolor Brushes
Before animal hair can be used in brush making, it undergoes an extensive preparation process.
Natural hair is carefully washed to remove oils and debris, then dried and sorted by length, thickness, and resilience. For high-quality brushes, the hairs are aligned so their natural taper forms the brush point. The tips are never cut, as trimming destroys the hair’s ability to hold a fine point.
Lower-quality brushes may use trimmed or mixed-length hair, which results in uneven performance and poor point retention.
Hand-Shaped vs. Machine-Cut Watercolor Brushes
One of the most important differences between student-grade and professional watercolor brushes lies in how the brush tip is shaped.
Premium round brushes are shaped entirely by hand. Artisans use moisture and gravity to coax the hairs into a perfectly tapered point. This method preserves the natural structure of the hair and allows the brush to hold more water and pigment.
Machine-made brushes are often cut to shape, which damages the hair tips and limits water capacity. These brushes tend to lose their point quickly and feel less responsive on paper.
Watercolor Brush Construction
- Hair or synthetic fiber tip
- Metal ferrule
- Handle
Hair or Synthetic Fiber Tip
Watercolor brushes are made with natural sable hair, synthetic sable fibers, or nylon. The very best are made with Kolinsky sable hair from a species of weasel in Siberia.
What Makes Kolinsky Sable Hair Special
Kolinsky sable hair is prized for its unique structure and performance. Each hair has a hollow core, allowing it to hold an exceptional amount of water while still releasing pigment smoothly and evenly. The natural scales along the hair shaft help guide paint from the belly of the brush to the tip.
Kolinsky hair comes from cold climates, which produce stronger, more resilient fibers. This is why these brushes have excellent spring, snap back into shape, and maintain a sharp point over time.
Ethical and Legal Considerations in Brush Making
Kolinsky sable hair is regulated under international wildlife protection agreements, which affects its availability and cost. Because of this, many manufacturers are now focused on ethical sourcing and developing high-quality alternatives.
Modern synthetic sable brushes have improved significantly in recent years. Advanced synthetic fibers are engineered to mimic the structure of natural hair, offering good water retention, durability, and consistent performance. These brushes are a popular choice for artists who prefer non-animal materials.
Metal Ferrule
Fine quality watercolor brushes are mounted into ferrules made of a hard but malleable, corrosion-resistant metal such as brass or copper. These are typically plated with nickel, silver, or (rarely) gold. Ferrules on cheaper brushes are made of softer aluminum or tin.
Why Ferrule Quality Matters
A well-made ferrule does more than hold the hair in place. It protects the brush from water damage by preventing moisture from seeping into the handle. Poorly fitted or thin ferrules allow water to collect inside, which can loosen the handle and cause cracking over time.
Seamless, properly crimped ferrules are usually found on higher-quality watercolor brushes and significantly improve longevity.
Handle
Better quality watercolor brush handles are made of seasoned hardwood that is sealed and lacquered for a high-gloss waterproof finish. Cheaper, mass-produced handles are made of unfinished raw wood. There are also brush handles made of molded plastic.
Short Handle vs. Long Handle Brushes
Most watercolor brushes feature short handles, which offer greater control when painting at a tabletop or desk. Long handles are more common in oil and acrylic painting, where artists often work standing at an easel.
For watercolor painting, short handles allow for precision and comfort, especially when working on detailed passages or smaller paper sizes.
Watercolor Brush Shapes
- Round – for a variety of brush strokes with a fine tip for details.
- Flat – for spreading paint quickly and evenly over a broad surface.
- Mop – for broad washes, soft paint application over layers and glazing.
- Rigger – useful for painting fine lines.
How Brush Shape Is Formed
Brush shape is determined during the hair alignment and shaping stage. In quality brushes, hairs are layered to create a full “belly” that holds water, while the natural taper forms the working tip. Poorly shaped brushes often lack this belly, resulting in frequent reloading and uneven strokes.
Watercolor Brush Sizes
There is a wide range of brush sizes from very small to very large, respectively:
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 18, 20, 22, 24, 25, 26, 28, 30.
The most frequently used are in the mid-size range: 6, 8, 10, 12, 14, 16, 18. The size indicates the width of the hair tip. The larger the size, the broader the brush stroke will be.
Why Brush Sizes Vary by Brand
Watercolor brush sizes are not standardized across manufacturers. A size 12 brush from one brand may be closer in size to a size 10 or 14 from another. Hair length, belly diameter, and taper all influence how a brush performs, which is why comparing brushes visually is often more reliable than relying on numbers alone.
Why Older Watercolor Brushes Often Perform Better
Natural hair brushes tend to improve with use. When new, brushes contain sizing that helps protect the hair during shipping. As this washes out over time, the brush becomes more responsive and flexible.
A well-cared-for brush often reaches a “sweet spot” where it holds more water, maintains a perfect point, and feels effortless to control.
How to Identify a Quality Watercolor Brush
When evaluating a watercolor brush, look for these signs of quality:
- Forms a sharp point when wet
- Snaps back into shape after bending
- Holds water without dripping
- Has evenly aligned hairs with no strays
- Features a solid, seamless ferrule
Recommended
Quality watercolor brushes are expensive but worth the investment. If you handle your brushes with care—rinse them thoroughly after a painting session, and store them flat or in an upright brush holder to dry—they will last you for many, many years.
To start, I recommend buying Blick Masterstroke Finest Red Sable Brush – Round, Size 8, Short Handle. My favorite and most frequently used sable brush is a Round, Size 12, Short Handle.