POWER BRUSH FINISHING Machinery's Handbook, 31st Edition
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Fig. 3. Setup for Brushing Broached Splines Fig. 4. Setup for Finishing Helical Gears Adjustments for Eliminating Undesirable Conditions in Power Brush Finishing Undesirable Condition Possible Adjustments for Eliminating Condition Brush works too slowly (1) Decrease trim length and increase fill density. (2) Increase filament diameter. (3) Increase surface speed by increasing R.P.M. or outside diameter.
(1) Reduce filament diameter. (2) Reduce surface speed by reducing R.P.M. or outside diameter.
Brush works too fast
(3) Reduce fill density. (4) Increase trim length.
(1) Decrease trim length and increase fill density. (2) If wire brush tests indicate metal too ductile (burr is peened rather than removed), change to nonmetallic brush such as a treated Tampico brush used with a burring compound. (1) Decrease trim length and increase fill density. (2) Decrease filament diameter. (3) Try treated Tampico or cord brushes with suitable compounds at recommended speeds. (4) Use auxiliary buffing compound with brush.
Action of brush peens burr to adjacent surface
Finer or smoother finish required
(1) Increase trim length. (2) Reduce brush fill density. (3) Reduce surface speed. (4) Increase filament diameter.
Finish too smooth and lustrous
(1) Devise hand-held or mechanical fixture or machine which will avoid irregular off-hand manipulation. (2) Increase trim length and decrease fill density. Polishing and Buffing
Brushing action not sufficiently uniform
The terms “polishing” and “buffing” are sometimes applied to similar classes of work in different plants, but according to approved usage of the terms, there is the following distinction: Polishing is any operation performed with wheels having abrasive glued to the working surfaces, whereas buffing is done with wheels having the abrasive applied loosely instead of imbedding it into glue; moreover, buffing is not so harsh an operation as ordinary polishing, and it is commonly utilized to obtain very fine surfaces having a “grainless finish.” Polishing Wheels.— The principal materials from which polishing wheels are made are wood, leather, canvas, cotton cloth, plastics, felt, paper, sheepskin, impregnated rubber, canvas composition, and wool. Leather and canvas are the materials most commonly used in polishing wheel construction. Wooden wheels covered with material to which emery or some other abrasive is glued are employed extensively for polishing flat surfaces,
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