Fill Material

The type of fill material used in industrial brushing tools as manufactured by United Engineered Products covers a wide range to accommodate all types of brush requirements. In designating fill materials for brushes, certain code letters are used. The code letters used for the three basic types of fill material, wire, plastic, and natural fiber, are shown in the tables below. Beneath each table, the physical characteristics of some of the more commonly used materials are listed.

Code Material
No Code Untempered Steel
SS Stainless Steel
K Premium Tempered Steel
B Brass
H Tempered Steel
PB Phosphor Bronze
M High Carbon Steel
NS Nickel Silver
  • Untempered steel wire – for routine work where severe cutting is not required.
  • Tempered steel – good cutting edges.
  • Special analysis high carbon – hard, good fatigue resistance.
  • Stainless steel – for brushing stainless or aluminum. Good non-corrosive propertles.
  • Phosphor bronze – non-sparking; for use in explosive atmospheres.
  • Brass – non-corrosive, soft.
Code Material
TN Tynex Nylon
L Lon Nylon
HN Herex Nylon
D Durastran
P Polypropylene
PS Polystyrene
  • Tynex nylon – has highest degree of wear resistance, bend recovery, not very abrasive.
  • Polypropylene – durable, resistant to moisture, more abrasive than nylon.
  • Polystyrene – abrasive but brittle and not too durable; inexpensive.
Natural Fiber
Code Material
WTD White Tampico (dry)
BH Bahia
WTT White Tampico (Regular Treatment)
BS Bassine
GT Grey Tampico
PM Palmyra

Fill Density

Fill density can be varied considerably. Two brushes of approximately the same diameter, face, and trim length may have a 100-percent difference in fill weight. Densely filled brushes are used where fast-cutting, uniform surface effects or finer surface finishes are required. An “open” structure is used when a whipping or flicking action is desired from the wire. This is obtained by using more deeply crimped wire. A fine crimped wire packs more and gives a more dense brush.


A short trim gives a hard, stiff brush that is fast cutting and rugged. A short trim provides better control of the brushing surface required for finer, more uniform finishes. Longer trim lengths are used to provide flexibility required when brushing irregular surfaces.


The horsepower required will depend on the surface speed at which the brush operates, the pressure the operator uses in applying the brush to the work, the area of the brush in contact with the work, and the coefficient of friction.

Brush Speed

The best speed at which a brush operates must be determined by the requirements of the particular job. The higher the rotary speed, the firmer and harder the brush will be because of centrifugal action. It is for this reason that fine wire brushes operated at high speeds act like coarser brushes at lower speeds. If experience is gained on a job with a certain diameter brush at a given speed, changes of operating conditions can be made without adverse effect by maintaining approximately the same surface speed. Approximate surface speeds for various brush diameters and rotary speeds are shown below.

Approximate Surface Speed (Ft./Min.)

Brush Diameter
RPM 4" 6" 8" 10" 12" 14" 15" 16"
900 950 1,400 1,900 2,350 2,800 3,300 3,350 3,750
1,500 1,550 2,350 3,150 3,900 4,700 5,500 5,900 6,250
1,150 1,200 1,800 2,400 3,000 3,600 4,200 4,500 4,800
1,750 1,800 2,750 3,650 4,550 5,500 6,400 6,800 7,300
2,000 2,100 3,100 4,200 5,200 6,300 7,300 7,800 8,400
2,400 2,500 3,800 5,000 6,100 7,500 8,800 9,400 10,000
2,800 2,900 4,400 5,850 7,300 8,800 10,200 11,000 11,700
3,000 3,100 4,700 6,300 7,800 9,400 11,000 11,800 12,500
3,200 3,350 5,000 6,700 8,400 10,200 11,700 12,600 13,400
3,450 3,600 5,400 6,700 8,400 10,200 11,700 12,600 13,400
3,750 3,900 5,900 7,800 9,800 11,800 13,700
4,000 4,200 6,300 8,400 10,500 12,500
5,000 5,200 7,800 10,500 13,100

Special Designs

United Engineered Products maintains a modern facility equipped with specialized equipment designed to allow evaluations of all types of brushing applications. We have tried to give you a guide to brush selection in the tables above. But we also welcome your inquiries and sample workpieces that can be studied at no cost to you by our United consultants.