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).
Instruction sheet detailing a report on dynamo brush wear after extensive mileage.
| Identifier | ExFiles\Box 60\1\ Scan134 | |
| Date | 4th March 1929 | |
| ROLLS-ROYCE LTD. INSTRUCTIONS. To___________________________19__ Order No. PD 41 (3) Customer's No.____________ Brush wear was as follows:- Position | Positive | Negative | Control Inner. | .010" | .008" | .012" Outer. | .016" | .013" | .012" Dynamo SS{S. Smith}2 on 21EX. These brushes were fitted 4-3-29, and have travelled 11,647 miles. From enquiries concerning their behaviour, Mr. Hancock stated that the brushes were not particularly noticed, but he thought they were no quieter than the standard. At the end of the test, when the machine was removed from the car, and run on the bench, the brushes appeared to be no quieter than the standard type. The commutator was found to be badly blackened in places. This may have been partly due to oil getting on to it as there was oil in the end-cover and on the end bracket, besides which, the surfaces of all the brushes were well polished as though little sparking had occurred. The inner control brush was found to be stuck in its holder due to a greasy mixture of oil and brush dust. Signed Cont'd This Sheet must be filed on completion of the work. | ||