Flat brushes are defined by a flat surface on which the brush material is mounted. They are generally fixed to the machinery structure, however in some cases they are attached to a moving part as well.
These brushes consist of a roller/ cylinder on which the brushing filaments are fixed on the curved surface of the roller/cylinder. This brush is then driven around its axis using a power drive for the brushing action.
Circular brushes consist of filaments continuously arranged in a circular pattern and supported between two side plates. They are power driven either by mounting them on a motor spindle or in a chuck using a shank.
End brushes, as the name suggests are brushes mounted on the end of a shaft/ shank which is mounted in a chuck/collet of a power tool. They are used for finishing features like slots, cavities and pockets.
TWIST IN BRUSHES
Twist in brushes are brushes where the filament material is twisted in between two wires. This type of brush is primarily used to finish the internal walls of tubes, pipes and cylinders.