... model1 004 336 801,09,10,13,14,20,21,27,28,31,42 51,53 937 ... scratch, rough, ablation and so on. (2) With a good flow properties and set to change commutation , ... and stable oxide film. Non-standard brush can be designed and be manufactured per buyer's drawing or sample. ... insure that the best machine electrical neutral can be achieved, the brush holders must be quartered. Quartering is setting the ...