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).
Diagram showing the dimensions of main and control dynamo brushes for various models.
| Identifier | WestWitteringFiles\O\2April1926-June1926\ Scan089 | |
| Date | 11th May 1926 | |
| 11.5.26. DYNAMO BRUSH DIMENSIONS. MAIN. CONTROL. Goshawk. .300 .750 .225□" .200 .750 .150□" EAC. .375 .500 .1875□" .500 .1875□" .275 .500 .1375□" .580 .1375□" EAC. (Narrower brushes). .280 .500 .140□" .500 .140□" .187 .500 .0935□" .500 .0935□" Not to scale EFC. | ||