From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Test report on the 10,000-mile performance of Morganite EG2 brushes on a dynamo.
| Identifier | WestWitteringFiles\T\2January1929-June1929\ Scan119 | |
| Date | 1st February 1929 | |
| PB.37 EFC. COPY. Contd. 10,000 MILES TEST OF MORGANITE EG2 BRUSHES. On 13.4.28, a set of the above brushes was fitted to dynamo I set to half way between the upper limit of standard output and the maximum permissible output; i.e. the peak output in a hot condition was 12.8 amperes. The commutator was then cleaned and all brush dust removed from the holders and end bracket, after which the machine was put on 9-EX. On this car it travelled 12,015 miles up to 1.2.29. From an examination of the machine, the brushes were found to be in an excellent condition. The surfaces of all the brushes were quite clean and highly polished with the exception of a very slight blackening on the control brushes. The commutator was blackened in placed while in other places the segments were quite clean. This suggests that the blackening was due more to a small quantity of oil getting on to the Commutator than to the grade of the brush. The inner control brush was stuck in its holder This is rather borne out by the fact that/as the result of oil getting on to it. The amount of carbon dust deposited was small. The wear of the brushes was found to be :- Brush. Positive. Negative. Control. Inner. .0065" .0055" .004" Outer. .005" .0075" .0095" Finally the dynamo was given a run on the bench in order to confirm that it had maintained its output. This was O.K. Generally, the results are considered satisfactory. EFC/C.A.Pignatt. | ||