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).
Letter from The Morgan Crucible Company regarding the performance of brushes on commutators and advising against material changes without testing.
| Identifier | ExFiles\Box 166\1\ img094 | |
| Date | 5th March 1937 | |
| -2- WH 2751 To The Morgan Crucible Company, Limited. Messrs. Rolls-Royce Limited, D E R B Y. 5th March, 1937. The duty which brushes have to perform on commutators is much more arduous than when they have only to collect current from a plain ring, and their performance in service is very sensitive to conditions. For instance, the oxide skin itself plays an important part in the brush behaviour. We should hesitate to replace a copper commutator by one of, any other material without first conducting thorough tests to ensure that some undesired or unexpected phenomenon would not result from the change. Yours faithfully, THE MORGAN CRUCIBLE COMPANY LIMITED. per:- P.V.B. | ||