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).
Methods to eliminate brake judder and the results of related tests.
| Identifier | Morton\M20.2\ img031 | |
| Date | 1st May 1924 guessed | |
| WE CAN ELIMINATE JAGGERS BY :- (1) Fitting some form of torque arm or parallel radius rods to the front axle. (2) Introducing an oil dashpot in parallel with the front brake operation; This makes it impossible to apply the brakes suddenly, and also increases the pedal pressure required. (3) Cutting off the leading 6" of Ferodo lining from the wrapping shoe. In doing this the braking effort is reduced to practically nothing. The same amount of Ferodo (6") has to be cut off the bronze flexible shoe also before jaggers are eliminated. While carrying out this experiment it is interesting to note that no difference in the violence or period of jaggers occurred as the Ferodo was cut away. The jaggers were as violent when 5" of Ferodo had been removed as with the full shoe, but when the sixth inch was removed, jaggering entirely vanished. From these tests we can definitely say that jaggers are not caused or affected by :- (a) Type of front suspension used. (b) Distortion of axle, brake carrier or wheels. (c) Method in which pressure is applied to drums. (d) Flexibility or type of brake shoe used. ********************* | ||