The Ultimate Guide to Brushes and What They Do

• Posted on 14 March 2025
• By Jennifer Boe
• 0

Brushes are more than just tools—they are an extension of the artist's vision and technique. Whether you’re choosing your first set of brushes or looking to expand your collection, understanding their types, uses, and proper care will enhance your painting experience. Investing in quality brushes, maintaining them with care, and experimenting with different types will open up a world of possibilities for your art.

Brush Construction: A Timeless Craft

Brush construction is a fascinating process that remains intricate even in our age of technology. The heads of natural brushes are shaped entirely by hand, and the tips are the natural ends of the hairs—nothing is trimmed from the tip. Any shaping is done to the side of the hair that is bound within the ferrule.

Brushes are composed of three main parts:

Tuft of hairs (natural or synthetic) arranged and cemented into the ferrule

Ferrule, the metal piece that holds the hairs in place

Handle, which varies in length and material

High-quality brushes have seamless ferrules to prevent solvents from leaking inside, which can damage the brush.

Choosing the Right Brush for the Medium

Brush selection depends on the type of media you’re using, but ultimately, it comes down to personal preference. Here are some tips to guide your selection:

Handle Length:

Long-handle brushes are ideal for oil and acrylic painting, allowing you to paint vertically from a distance for a broader view.

Short-handle brushes are best for watercolor painting, which requires a closer, more controlled approach.

Natural vs. Synthetic Hairs:

Acrylic Paint: Acrylics dry quickly and can damage natural brush hairs, making synthetic brushes a great choice.

Oil Paint: Bristle brushes are often recommended for beginners since they’re economical and hold a good amount of paint.

Watercolors: Natural soft-hair brushes are recommended as they absorb water well, aiding in smooth washes.

Brush Filaments: Natural vs. Synthetic

Understanding filament types helps you choose the best brush for your painting needs:

Kolinsky Sable: The highest quality, sourced from mink tails. Offers excellent spring and a fine point.

Red Sable: From the weasel family, these brushes provide smooth strokes with great responsiveness.

Sabeline: A more affordable ox-hair alternative to red sable, offering similar performance.

Ox Hair: Soft, liquid-holding bristles from cattle and boar ears, though they lack a fine tip.

Bristle: Stiff pig or boar hair, ideal for oil painting. Natural split tips hold paint well.

Camel Hair: Despite the name, this brush contains squirrel, goat, or pony hair. It’s soft but harder to control.

Synthetic: Made from nylon or polyester, these brushes mimic natural hair while being more durable, easier to clean, and budget-friendly.

Yes, the store does have a small handful of real sable brushes in stock, but we have chosen not to restock them moving forward. We are focusing on high-quality synthetic alternatives that offer excellent performance while being more sustainable and affordable. Also, sables are cute AF. See evidence below: 

Brush Sizes Explained

Brushes come in a range of sizes, from very small (multiple zeros) to large double-digit brushes. For flat brushes, the size refers to the width of the ferrule. However, round brush sizes can vary by manufacturer, so it’s best to choose by visual inspection rather than relying solely on the printed size. When getting started, pick brushes that look right for your work rather than focusing on the number.

Brush Shapes and Their Uses

Different brush shapes are suited for various techniques:

Round brushes are an extremely versatile. They’re perfect for detail work and thicker strokes. They come in various shapes:

Round: These brushes are great for small details or filling in large areas depending on how much pressure you apply and the brush size. Larger round brushes can hold quite a bit of water in the belly of the brush but still end in a fine tapered point. This allows for a variety of strokes and the ability to move from large coverage to tight detail without having to dip back into the paint often.

Liner: Long hairs allow for consistent thick-to-thin strokes, making them great for fine details, lettering, and continuous lines.

Spotter: Designed for highly detailed work, perfect for miniature painting and precise lines.

Quill: Large belly holds more paint, making it ideal for washes and broad strokes.

Flat brushes are great for filling in large areas of color, painting straight lines, and blending. The flat family includes:

Flat shaders: Longer than a chisel blender, excellent for filling large areas and creating thin lines with the chiseled edge.

Filbert: A rounded tip softens edges, great for blending, dry brushing, and organic shapes like petals or clouds.

Angular shader: The angled tip provides crisp edges, precise control, and smooth blending in tight areas.

Wash/Glaze: A must-have for base coats, broad strokes, and covering large areas efficiently.

Specialty brushes are great for creating things like grass, fur, or clouds. Here are some of the most typically used shapes:

Fan: Blends and softens strokes; also used dry for textures like hair, trees, and grass.

Deerfoot or Round Blender: Pouncing or tapping creates fur, foliage, and repetitive patterns.

Grainer: Thin, spread-out hairs help paint fur, grass, and textures with cross-hatching effects.

Dagger Striper: Great for straight lining, cross-hatching, and thick-to-thin strokes. 

Mops: Best for blending, moving low-viscosity paint, and soft wash applications.

How to Buy Quality Brushes

Buying a high-quality sable brush is a significant investment, so make sure it’s worth the price. A simple test can help:

1. Dip the brush in water and flick it against your wrist to loosen any protective glue.

2. Swirl it in water until thoroughly soaked.

3. Snap your wrist to discharge the water—the brush should come to a perfect point, and the hairs should spring back without flopping over.

Find the Perfect Brush at KCAI Underground

Explore our selection at the KCAI Underground Art Store! You are welcome to try before you buy. From synthetics to the finest Kolinsky sables, discover the perfect tools to bring your artistic vision to life.