Brake leverage recommendations, testing, and the effects of wear.
| Identifier | WestWitteringFiles\T\2July1929-December1929\ Scan144 | |
| Date | 2nd November 1929 | |
| To R. {Sir Henry Royce} from Hs {Lord Ernest Hives - Chair} /An. c. Sg. {Arthur F. Sidgreaves - MD} c. Wor. {Arthur Wormald - General Works Manager} E. {Mr Elliott - Chief Engineer} c. Da. {Bernard Day - Chassis Design} By. {R.W. Bailey - Chief Engineer} ORIGINAL Hs {Lord Ernest Hives - Chair} /AnS/ADL2.11.29. BRAKE LEVERAGES. X7260 The brake leverage that we recommend is [Diagram of a brake leverage system with values '35° Cams' and '1.725'] The direct braking without the servo is sufficient for shunting. The altered cam angle gives slightly more front braking with the servo in action. We mentioned the effect of wear on the pedal travel in our Hs {Lord Ernest Hives - Chair} /RnS/LG29.5.29. There is no doubt that our being forced to reduce the proportion of front braking to avoid squeaks has increased the feeling of sponginess on the pedal and also increased the maximum temp. that the rear drums are likely to attain on exceptionally steep gradients. We should like to run the next 10,000 miles test with the altered leverage to the rear brakes and sufficient lining on the shoes to ensure that after five notches wear the toggles can be adjusted to give another five notches wear before the brakes are worn out. | ||
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).