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).
Investigating the cause and cure for brake 'jaggers'.
| Identifier | ExFiles\Box 30\6\ Scan170 | |
| Date | 28th January 1924 | |
| R.R. 403A (40 H) (SL 42 12-7-23). J.H., D.{John DeLooze - Company Secretary} EXPERIMENTAL REPORT. To R.{Sir Henry Royce} from HS.{Lord Ernest Hives - Chair} c. to CJ. RG.{Mr Rowledge} c. to DA.{Bernard Day - Chassis Design} E.{Mr Elliott - Chief Engineer} c. to BY.{R.W. Bailey - Chief Engineer} WOR.{Arthur Wormald - General Works Manager} Expl. No. 9940 REF: HS{Lord Ernest Hives - Chair}3/LG28.1.24. S E C R E T. BRAKE JAGGERS. After we had run the floating fulcrum brakes on the test rig we put them back on the chassis and found that the running had increased their efficiency considerably. We also found with these brakes that we could obtain jaggers equally as bad as we have had with fixed fulcrum brakes. This leaves us now with - torque arm - rods - or dash pot as the definite cures for jaggers. We have tried stiffer brake drums but found that it made no difference to the jaggers. The tendency for a car to jagger is very elusive. We can run a car for 1,000 miles with no trouble, then on one occasion it will occur. When it does occur it causes such a nerve shattering noise that we could never feel happy if there was any risk of it occurring when the car was in customers' hands. We are carrying out tests to see if we can obtain a similar effect on the Isotta or Hispano cars if we operate the front brakes only by the foot pressure. HS.{Lord Ernest Hives - Chair} | ||