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 experimental tests on various brake linings.
| Identifier | WestWitteringFiles\S\June1928-August1928\ Scan129 | |
| Date | 1st August 1928 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to BJ. Wor.{Arthur Wormald - General Works Manager} c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to BY.{R.W. Bailey - Chief Engineer} ORIGINAL Hs{Lord Ernest Hives - Chair}/Rn{Mr Robinson}8/LG24. 8. 28. BRAKE LININGS. x719v x 4466 We have been trying experimentally all sorts of brake linings for the past three years. They can be divided up into three groups :- (1) Soft linings. We ran some Ferobestos linings. These were very soft, had a fairly high coefficient of friction, and seemed slightly better than our standard material for brake squeaks. They proved unsatisfactory, because they had insufficient life. (2) Intermediate. Linings comparable for density with our standard Ferodo. We tried various types of Ferodo with low coefficients of friction; some even impregnated with graphite with a view to overcoming brake squeaks but they were no good. We tried Tenoid grade 'F' but it was bad for squeaking. Finally we have run Tenoid 'P' which gives us very consistent braking, is better than Ferodo for squeaking, and appears to wear as well as our standard material. (3) Hard linings. Harder grades of Ferodo, Tenoid T., and Raybestos all proved bad for squeaking. In addition Raybestos scored the drums very badly. As a result of our tests we recommend that a small quantity of Tenoid 'P' lining is tried out on production, as so far it has definitely shewn more desirable contd:- | ||