Everything You Need to Know About Brushes

This is one of Emma’s lovely illustrations

My illustrator friend Emma Block recently launched a collection of gouache brushes with the brand ProArte. She was kind enough to send me a set to try. My favorite thing about trying these brushes was getting another artist’s perspective on what they use to create their work.

I used Emma’s brushes to paint this Paris waterfront illustration and I gotta say - they were pretty amazing!

So this got me thinking - what makes a good brush? And how do you find your ideal set of brushes? And would I make any changes to the brushes I use now that I’ve tried another artist’s brushes?

For the sake of this article, I’m going to be focusing on brushes for the most common mediums illustrators use - acrylic, watercolor and gouache (simply because that’s what I know). That’s what Emma uses as well.

Emma’s brush set includes:

• Round brush size 2

• Round brush size 4

• Round brush size 5

• Filbert brush size 4

• Angled brush 1/4

She collaborated with the brand ProArte, but thankfully brush sizes are pretty standard across all brands, so you might even have some of these sizes at home.

What I’ve been using:

5 years ago, I wrote this article covering the 5 synthetic brushes I used the most:

• Spotter brush size 5

• Liner brush size 2

• Round brush size 10

• Flat shader brush size 4

• Flat shader brush size 10

And these are still the brushes I’ve been using. Comparing the brushes Emma uses with the brushes I use side-by-side, there are a few commonalities:

1. 5 is a magic number for a set of brushes, where you get just enough versatility. However, it’s still a pretty minimalist approach. I don’t like using a lot of brushes, because it makes painting feel more chaotic.

2. Synthetic brushes are best for gouache, watercolor and acrylic. You can’t beat the smooth, bouncy bristles.

3. About half your brushes should be for detailing and half should be for filling in larger areas. For me, I’ve been using two detail brushes (liner and spotter). For Emma, she has three in her set (3 sizes of smaller round brushes).

4. Brush sizes 2-5 are the most versatile for illustrators.

5. Emma and I both prefer longer handled brushes to shorter ones.

So now that I’ve used Emma’s brushes, would I make any changes to the main ones I use? The answer is a resounding YES!

The ones I would keep in my arsenal are just due to stylistic differences between mine and Emma’s work. If you’re a beginner looking for a set of brushes for gouache, watercolor or acrylic, I would HIGHLY recommend Emma’s set. It’s much more well-rounded and versatile than what I’ve been using. Also, you cannot beat the quality of Emma’s set.

After trying out Emma’s brushes and using the information I already know about the brushes I like, here are the 5 brushes I would probably use in the future:

• Emma’s Round brush size 2 (for detail work): After trying Emma’s brushes, I’ve been converted from a spotter brush to this one. I really enjoyed this brush because it allowed me to get really small details like I do with my spotter brush. However, the longer bristles and slightly bigger size made it much more versatile. I used this brush for the people in my illustration as well as the dots on the walls.

• Liner brush size 2 (for detail line work): My art has a lot of intricate line work, so I can see myself going back to my old friend. It reminds me of the kind of brush you use to apply eyeliner. The bristles are really long, so you get a straight, thin even line. For example, I would use this brush for the black line work on the buildings.

• Emma’s Filbert brush size 4 (for larger, looser areas): I would definitely swap out my round brush size 10 for this one from Emma’s set. When I started using this brush, it was love at first brushstroke. It worked great for fluffy areas like trees and clouds. I realized maybe my work had been missing this brush all along!

• Flat shader brush size 4 (For larger, geometric areas): This is probably my favorite brush of all time, so I had to leave it in the mix. It’s so similar to the angled brush from Emma’s set, but I’m simply used to the flat top versus the angled top. Both would be great choices. It’s just a matter of preference and the style of your work.

• Flat shader brush size 10 (For very large blocks of background): I use more solid, thick, large backgrounds in my work than Emma, so I’m keeping this brush in the mix for filling in larger areas like sky and water. The bigger brush size saves me a lot of time when blocking in large areas of color.

So how can you take this list and find the right brushes for you? Well, firstly it’s all about the size of the work you’re creating. Emma and I paint smaller, so if you like to paint larger, you may want to go up a size. If your work is all about detail, maybe your brushes will be smaller than ours.

As a guide, I used my good old friend ChatGPT to cover the basics of brush shapes and sizes for illustrators. Here’s what it said:

1. Round Brushes

• Shape: Rounded tip, pointed end

• Use:

  • Versatile for lines (thin or thick)

  • Detail work and outlining

  • Filling small areas

• Illustration Use Case: Fine details, intricate patterns, lettering.

2. Flat Brushes

• Shape: Flat, square-ended tip

• Use:

  • Wide coverage and large areas

  • Bold, straight strokes

  • Broad washes and backgrounds

• Illustration Use Case: Background washes, large-scale elements, sharp-edged shapes.

3. Filbert Brushes

• Shape: Flat body, rounded edge (oval-shaped)

• Use:

  • Soft blending and smooth edges

  • Rounded marks, petals, foliage

  • Gentle, curved shapes

• Illustration Use Case: Organic shapes, blending and transitions, botanical illustrations.

4. Angular (Angle) Brushes

• Shape: Flat brush with slanted edge

• Use:

  • Precise angles and lines

  • Shading tight corners

  • Calligraphic strokes

• Illustration Use Case: Geometric designs, lettering, precise edges.

5. Fan Brushes

• Shape: Flat, spread-out bristles in a fan shape

• Use:

  • Texture effects (trees, grass, hair, fur)

  • Soft blending

  • Scattering effects

• Illustration Use Case: Texture-heavy scenes, natural landscapes, abstract effects.

6. Liner (Rigger) Brushes

• Shape: Extremely thin, elongated bristles

• Use:

  • Thin, continuous lines

  • Detailed outlining

  • Fine calligraphy or delicate patterns

• Illustration Use Case: Hairlines, intricate line art, delicate details.

7. Mop Brushes

• Shape: Soft, fluffy, rounded brush

• Use:

  • Large washes and color blends

  • Smooth gradients

  • Watercolor techniques

• Illustration Use Case: Backgrounds, skies, smooth color blends.

Brush Sizes

Brush sizes typically range numerically from 0000 (smallest) to 24+ (largest). The actual physical size can vary between brands, but here's a general guide:

• Sizes 0000–2 (Very Small):

  • Precise details, tiny illustrations, miniature works.

• Sizes 3–6 (Small/Medium):

  • General detailing, smaller areas, controlled strokes.

• Sizes 7–12 (Medium/Large):

  • Broad strokes, larger coverage, background areas.

• Sizes 14–24+ (Very Large):

  • Large canvases, extensive washes, broad backgrounds.

One of my favorite tests of a good brush is to see how they look on the shelf at the art store. Are the bristles neat and tidy, or are there a few out of place? They should most certainly be neat and tidy if you haven’t even used them yet. Also, does the handle feel durable? One thing I noticed about Emma’s brushes is how much better the handles felt than on the Princeton Lauren ones I’ve been using. They felt like they would really stand the test of time, versus chipping like mine do.

Again, if you’re interested in purchasing Emma’s brush set, you can find it here.