Not all synthetic paint brushes are made the same. In a recent Trekell live webinar, Pro Team Artist Eric Johnson went under the microscope to show how filament diameter, taper and texture affect the way a brush performs on the canvas.
Walk into an art store and you will likely find dozens of synthetic brushes that appear nearly identical at first glance. The meaningful differences, however, are often hidden inside the brush head.
Although Eric demonstrates these brushes primarily in oil paint, the same construction details, including filament diameter, taper, texture and spring, help explain how synthetic brushes feel across many painting mediums.
Not All Synthetic Brushes Are Built the Same
Modern synthetic brushes are much more sophisticated than simple plastic fibers. The type of filament used, how it is shaped and how multiple filaments are combined all influence the way a brush holds paint, releases paint and responds while you work.
During the webinar, Trekell owner Courtney Bridges explained that Trekell synthetic brushes are made using Thermyx™ filament. Unlike traditional nylon, Thermyx is designed to retain its original shape while providing consistent spring and memory.
“All of our synthetics are made from a filament called Thermyx. It’s similar to nylon, but the difference is it’s going to hold its shape better than a nylon brush.”
Rather than relying on one identical fiber throughout a brush head, premium synthetic brushes can combine varying filament diameters. Finer filaments contribute softness and responsiveness, while thicker filaments provide more strength for moving paint.
That variation helps a synthetic brush offer a more nuanced painting experience while maintaining the consistency and reliability artists expect from modern materials.
Why Tapered Filaments Matter
One of the most revealing moments of the webinar came when Eric placed several brush heads under a microscope.
At high magnification, entry-level synthetic brushes may use more uniform filaments with blunt-cut tips. Higher-quality synthetic brushes can feature tapered filaments that gradually narrow toward the end of each hair.
That taper affects more than appearance. It helps a brush come to a cleaner point, create controlled edges and release paint with greater sensitivity.
“The finer the brush hair, the softer the brush is going to be.”
Why Filament Diameter Changes Everything
Softness is not determined by brush size alone. The diameter of each individual filament plays a major role in how a brush feels and performs.
Finer filaments generally create a softer brush that moves gently across the surface. Thicker filaments have more strength and can push heavier paint with more authority.
During the microscope demonstration, Eric compared Trekell Golden Taklon and Spectrum brushes. Spectrum uses finer filaments, making it technically softer, while Golden Taklon has a more aggressive taper at the tip. In Eric’s oil painting process, that taper makes Golden Taklon especially useful for delicate, oily glazes and subtle transitions.
Spectrum, meanwhile, remains a favorite for smooth, even passages of paint where a painter wants a soft brush with enough structure to lay down a more solid application.
Texture Matters Too
Not every synthetic filament has a perfectly smooth surface. Some Trekell brush families use textured filaments designed to recreate aspects of the handling of natural hair.
These subtle ridges affect how the brush holds and releases paint. They can give an artist more control and a more natural-hair-inspired response than a smooth synthetic filament.
“The filament itself has little ridges in it which simulates the handling of a natural hair brush.”
For example, Sienna synthetic Kolinsky sable and Legion synthetic mongoose brushes offer a different feel from smooth-filament brush lines such as Golden Taklon and Spectrum. They are still soft brushes, but they have more resilience and are useful when an artist wants a little more authority in the mark.
What This Means on the Canvas
Brush construction affects more than how a brush looks in its package. It affects the marks you can make, how much paint the brush can move and how the brush responds to pressure.
- Finer filaments: Generally create a softer feel for gentle blending and subtle transitions.
- Thicker filaments: Provide more strength for moving heavier paint and creating more assertive marks.
- Smooth filaments: Help paint glide and diffuse easily for soft, refined passages.
- Textured filaments: Offer a more natural-hair-inspired feel and more paint-handling authority.
- Tapered tips: Help create controlled edges, refined details and a responsive point.
Find the Right Synthetic Brush for Your Process
There is no single best synthetic brush for every artist or every stage of a painting. The best choice depends on the surface, the viscosity of your paint and the type of mark you want to make.
- Golden Taklon: A smooth, responsive option for delicate glazing, soft transitions and controlled detail.
- Spectrum: A soft brush with enough structure for even passages of paint and refined application.
- Sienna: A synthetic Kolinsky sable option with a natural-hair-inspired feel and controlled resilience.
- Legion: A synthetic mongoose option with more authority for painterly marks, highlights and controlled texture.
- Mop: A soft synthetic mop brush for blending, softening edges and reducing unwanted paint ridges.
Eric often uses soft brushes when he wants a polished, smoother application, while more resilient brushes help preserve texture and visible brushwork.
Modern Synthetic Brushes for Soft Blending
Soft natural-hair brushes have long been valued for their ability to blend and soften paint, but they can also shed hairs into a painting and become difficult to maintain over time.
Modern synthetic alternatives, including synthetic mop brushes, are designed to provide a soft, fluffy feel for blending while offering more consistent shape retention and reduced shedding.
Used with a light touch, a mop brush can gently soften an edge, blend a transition or reduce unintended paint texture without aggressively scrubbing the painting surface.
The Bottom Line
Brush shape is only part of the decision. Filament diameter, taper, texture and spring all influence how a synthetic brush holds paint, releases it and responds on the surface.
Once you understand those differences, choosing a brush becomes less about finding one universal “best” option and more about selecting the tool that supports the marks you want to make.
Watch Eric Johnson’s full demonstration above to see Trekell soft synthetic brush lines under the microscope and in action on the canvas.
Explore Trekell’s Synthetic Brush Collections
Whether you are looking for soft blending brushes, versatile all-purpose brushes or resilient brushes for moving heavier paint, Trekell offers a synthetic brush line for every stage of your process.