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).
Modifying brake shoes to eliminate squeaks on the 40/50 HP lightened axle.
| Identifier | ExFiles\Box 26\4\ Scan316 | |
| Date | 15th December 1926 | |
| To R.{Sir Henry Royce} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to Ev.{Ivan Evernden - coachwork} Wor.{Arthur Wormald - General Works Manager} c. to RG.{Mr Rowledge} E.{Mr Elliott - Chief Engineer} c. to BA. BY.{R.W. Bailey - Chief Engineer} X5409 X719 Hs{Lord Ernest Hives - Chair}/Rnl/LG15.12.26. 40/50 HP. BRAKE SQUEAKS. X5409 x8470 During our recent trouble with brake squeaks on the 40/50 lightened axle, we tried various alterations to the flexibility of the brake strap with a view to solving the problem. We found that when we cut away the centre section of the shoe towards the heel as in the attached sketch, the brake squeaks were practically eliminated. The method used for test was to take the standard shoes off a car that was squeaking badly, alter them as per sketch and replace them. In every case this effected a pronounced improvement which was maintained. This improvement varied from 100% cure to 70% cure with different cars. Merely lightening the shoes by drilling did not have the same result. The position for the flexibility was evolved from tests carried out by C.W.Hancock on brake bedding. The shoes which have run some thousands of miles, do not seem to suffer in any way from their reduced strength, nor is the braking impaired. We have had a w case of front axle jagger with them however. We cannot yet say whether the lining will wear evenly with these shoes but are continuing the tests. Although it may not be considered desirable to proceed further with such a shoe, we believe that the test has demonstrated that we can materially lighten brake contd :- | ||