Maintenance of Good Brusk Performance

It is difficult to say what is the most important characteristic of a carbon brush. The property which makes a brush grade the ideal selection for one application may be of secondary importance on another. For heavy duty service it seems preferable that those characteristics which aid or permit the maintenance of a uniform surface film on the commutator should be given first consideration. Particular attention should be given to the ability of the brush to maintin close contact with the commutator or ring surface. In addition to care in the selection of brush grade, equal attention should be given to the initial preparation of the commutator or ring surface, avoidance of high or feather-edge mica, accurate machine adjustment, careful brush installation, maintenance of correct and uniform spring pressure, and periodic use of the canvas wiper. Such routine care costs little but aids greatly in maintaining good brush performance at minimum expense. Finally, at the first indication of unsatisfactory performance, an effort should be made to determine the primary fault and to correct it in time to prevent serious disturbance of operation.