Brush Design Specifications - Brushes 101


Brush density and length of fill material are important characteristics for designing your brush tool. Brush density appearance can be affected by the filament shape and can be produced with a round crimp, round level (straight) or rectangular shape.

Filament Close Up Brush Contact

Round crimp has a wave in the filament which provides a denser brush appearance and produces a continuous and more even brushing action. Crimp is measured by the amplitude, depth of the crimp and frequency and number of crimps per inch.

Crimped

Level or straight fill provides a less dense appearance. The exposed view of the filament is known as the trim length and is the working strength of the brush.

Straight

Rectangular fill material applies approximately 18 times more abrasion on a surface because it makes solid line contact. It works best for heavy-duty applications.

Rectangular

When determining the exact filament characteristics your application requires, many aspects must be addressed. The filament’s diameter, trim length and density will determine the aggression, surface penetration, flexibility and speed of the power brush. The mounting component is the other design consideration of power brushes and it is important to use the largest diameter power brush your equipment can handle.

The filament diameter affects the aggression of the brush. Thicker filament is more aggressive because it has more weight to support the brushing action. Trim length is important as longer trim equals a less aggressive but more flexible brush, ideal for hard-to-reach areas. Short trim lengths are more aggressive but less flexible and are great for areas requiring accurate brushing.

Brush density and length of fill material are important characteristics for designing your brush tool. Heavy density fill allows for more contact points, increasing the brushing action and extending the brush life. Brush density appearance can be affected by the filament shape and can be produced with a round crimp, round level (straight) or the abrasive fill also can be produced with a rectangular shape. Crimped wire provides more even breaks and a lighter more flexible brushing action.

  • Round crimp has a wave in the filament which provides a denser brush appearance and produces a continuous and more even brushing action. Crimp is measured by the amplitude, depth of the crimp and frequency and number of crimps per inch.
Crimped
  • Level or straight fill provides a less dense appearance. The exposed view of the filament is known as the trim length and is the working strength of the brush.
Straight

COIL WOUND ROTARY BRUSHES

Tanis has eight standard backing sizes for our metal back strip brushes – #2 ½ , #3, #4, #5, #7, #8, #10, #16 – ranging from .114” high x .098” wide to .688” high x .624” wide. The standard backing materials include galvanized and stainless steel. Brass and aluminum backing can be available upon request. For special sizes and tolerances, please contact our technical sales and engineering staff.

Coil Wound Rotary Brushes

Tanis can assemble coil wound rotary brushes to a core, a shaft or supply the coil unassembled for mounting on installed equipment. The shafts can be machined to customer specifications and core diameters with few design limitations, however weight can be a factor in the final assembly. Since most coils are welded directly to a tube or shaft, end rings can be machined for a better cosmetic appearance. If a more economical finish is desired, we can leave the weld and channel exposed.

We offer refurbishing services for coil wound rotary brushes on an existing shaft or tube by removing the worn brush and refilling the shaft or tube with a new coil wound brush. Tanis can also repair journal or stub ends on shafts to provide a new surface for drive side and bearings.

STAPLED SET ROTARY BRUSHES

Stapled set rotary and wheel brushes are manufactured by inserting individual tufts of filament into a drilled hole in a block of plastic and securing with a staple. The staple is made of steel or nickel-silver which is predicated by the environment and the conditions the brush will be performing under.

Stapled set rotary and wheel brushes are manufactured by inserting individual tufts of filament into a drilled hole in a block of plastic and securing with a staple. The staple is made of steel or nickel-silver which is predicated by the environment and the conditions the brush will be performing under.

Rotary Patterns

Generally, the tuft holes are drilled and filled vertically but depending on the application, the hole can be drilled and the filament inserted at an angle. The brush filament is trimmed in the final processing stage to provide a consistent, uniform brush face.

HOLE PATTERN AND DESIGN

Using the latest in machining technology, stapled set brushes can be designed and manufactured in virtually any hole or tuft pattern to produce a desired density and brush pattern. Our automated stapling machines can read CAD programs without requiring endless hours of programming on the machine. Small quantity and single tufted patterns can also be manufactured on a semi-automatic or hand machine.

Staple Design

The two most common hole patterns for flat stapled set brushes are a straight or staggered pattern but two additional patterns, spiral (helical) and chevron (herringbone), are available for rotary stapled set brushes. A spiral or herringbone pattern is used to orient product in a specific direction or used to give a specific brushing effect.

Rotary Patterns

CORE CONSTRUCTIONS

Solid block and core materials most commonly selected are wood and plastics including polyvinyl chloride (PVC), polypropylene, high-density polyethylene (HDPE), ultra-high molecular weight (UHMW), ABS and delrin. Flexible materials like soft, flexible polyvinyl chloride and urethane are also available. These backing materials allow the bending and contouring of the brush around a corner or radius.

STAPLES

The staple shown in the illustration is a primary part of the brush. A staple is made either of steel, stainless steel or brass. The type of staple is predicated by the environment and conditions the brush will be performing under.

Staples Fill Staples

HOLE OR TUFT DIAMETER

The individual hole or tuft diameter can range from, but not limited to, .078” up to 7/16”. The hole depth depends on the diameter of the hole or tuft diameter. The hole depth will help determine the block or core wall thickness required for the brush design. Generally the tuft holes are drilled and filled vertically. Depending on the application, the hole can be drilled and material inserted at an angle. The material can be angled in two ways either flared or converged.

Tanis has nine standard backing sizes for our metal back strip brushes – #2, #2 ½ , #3, #4, #5, #7, #8, #10, #16 – ranging from .114” high x .098” wide to .688” high x .624” wide. The standard backing materials include galvanized and stainless steel. Brass and aluminum backing can be available upon request. For special sizes and tolerances, please contact Tanis.

Our fully customizable stapled set strip brushes are available with flexible or rigid PVC backing and the range of lengths, shapes, trims and sizes is unlimited. We produce many standard stapled set strip brushes to fill immediate needs and also have continuous rolls of 50’ or 100’, which can be cut onsite to meet exact length requirements.

Metal Back
Strip Design

BRUSH DIAMETER

The diameter of the twisted brush will vary within the different constructions and range from .020” up to 8”. Brushes can be stiffened by either shortening the trim length or using a larger diameter bristle, or the brushes can be softened for an extended life by using a smaller bristle diameter. This diameter determines the classification of the brush.

BRUSH PART LENGTH

The brush part is the working function of any twisted brush. Generally the brush part is only on one end of the brush, but you can elect to have the brush part centered with stem wire on either side. Another choice, depending on the stem construction, is having a brush part on both ends. Your made-to-order brush can have a brush part varying from 1/2” or larger.

STEM MATERIALS AND CONSTRUCTION

There are other twisted brush characteristics that need to be determined to find the most effective brush for your application needs including stem material, stem gauge/diameter and overall length of the brush. The most common stem wire materials used are galvanized steel and stainless steel, although brass stem wire is also available.

The stem gauge is the diameter of the stem wire construction when twisted together. The stem wire after the brush part is often referred to as the handle length. Overall length is measured from the tip of the brush part length to the end of the brush and can range from 3/4” or larger. We offer various accessories to extend the overall length including a plastic tube, steel tube, hex-shank, threaded coupling or wood or plastic handle, which can be attached to the stem wire.

BRUSH TIP STYLES

Twisted brushes can be machined with many different brush tip styles, depending upon the stem construction and fill material selected. For example, a twisted brush with wire filament is not best suited for a turned tuft brush tip.

Below are the most common brush tip styles:

Continuous End

Continuous End

Broken End

Broken End

Turned Tuft

Turned Tuft

Vinyl tip

Vinyl tip

Tied Tuft

Tied Tuft

The overall length of your paint brush is made up of the handle and filament trim length. Another important characteristic is the width and the thickness or density of the brush part, as this will determine coverage and the amount of strokes it will take to coat a surface. The more densely filled the brush is, the more paint or liquid it will apply per stroke.

The handle of the brush is often made from wood that can be provided unfinished or finished with an applied paint or lacquer. The length of the handle can vary from extremely short to very long and ideal length depends on the brush use. If the brush is going to be used for detailed touch-ups, a short handle is recommended for optimal handling and control, but if the brush is used for stenciling large sign, a long handle is more effective.

Length of fill material is an important characteristic for choosing your paint brush. Shorter filament will provide a much stiffer and more controlled brushing action, effective for small surface applications and hard-to-reach areas. Longer filament will have the ability to transfer liquids and substances more efficiently and clean larger surfaces.

The overall length of your parts cleaning brush is determined by the length of the handle and the filament trim length.

The handle of the brush is often made from wood that can be provided unfinished or finished with an applied paint or lacquer. The length of the handle can vary from extremely short to very long depending on the brush use. For example, if the brush is going to be used for detailed touch-ups, a short handle is recommended, but if the brush is used for applying liquid to a large area, a long handle is more effective.

Length of fill material is an important characteristic for choosing your parts cleaning brush. Shorter filament will provide a much stiffer and more controlled brushing action, effective for small surface applications and hard-to-reach areas. Longer filament will have the ability to transfer liquids and substances more efficiently and clean larger surfaces.