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).
Results of testing Ferodo brake linings, detailing issues with overheating and noise.
| Identifier | ExFiles\Box 26\4\ Scan018 | |
| Date | 21th July 1914 | |
| 100A (150 II) (W.W. 529. 5-7-14) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 6870. COPY. To By.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} Copy to J.{Mr Johnson W.M.} Copy to Na.{Mr Nadin} Copy to Wor.{Arthur Wormald - General Works Manager} R10/P 21. 7. 14. x719 Brakes. I have today (20.7.14) tested the ferodo lining on the brakes. This seems to work quite well with one exception, that is, the heating of the brake drums seems to be v-ery quick and the expansion of the drum appears to be a large amount. It also appears to me that when the brake drum is hot, it is possible that the co-efficient friction may get less, although why this should be, I cannot give a reason. If this is not so, it seems as though we could increase the relative motion of the brake shoe to that of the pedal, and therefore be less effective by this expansion. We trace the noise of bubbing of the brake drum to the aluminium guard, which we think might be tested as a simple flat pl plate, instead of turning over in the present way. If it is necessary to turn it over, as was thought at the time of designing, it should be increased in diameter, so that the brake drum does not rub upon it when expanded. My method of testing the brake was to run the engine in gear at a fairly fast speed, applying the foot brake only to control the car on the level, and I am not sure how the cast iron liners would behave under this treatment, and also how our old central brake would stand this treatment. It is for this reason I asked you to make comparisons as it appears that these ferodo brakes are much too soon put | ||