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).
Account of experimental work done to eliminate brake squeaks.
| Identifier | ExFiles\Box 120\2\ scan0179 | |
| Date | 12th July 1937 | |
| Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} Rm{William Robotham - Chief Engineer}/AFM{Anthony F. Martindale}12/R.12.7.37. BRAKE SQUEAKS. The following is an account of experimental work we have done, and intend to do, in trying to eliminate the above complaint. At various times, recently, when we have had a car squeaking badly, we have tried the following:- (1) Lagging the carrier plate. (2) Lagging the drum and back plate. (3) Both the above together. (4) Weakening the shoes. (5) Fitting floating dampers to the shoes. (6) Fitting more rigid drums (to a car with weak drums.) (7) Examining brakes for slack in bushes with a view to eliminating it. There is normally no slack. (8) Reducing the arc of contact between lining and drum (this usually makes squeaks worse.) (9) Altering the tipping shoe setting, either as regards poundage or clearance. (10) Fitting spring bands round the drum. None of the above makes any permanent difference, although for a few miles after upsetting a brake, it is usually silent. The only way of stopping a brake from squeaking is to change the liners, but as these in turn achieve the condition of the original liners, this is not a permanent solution. Similarly, filing the liners stop squeaks, but very temporarily. We have come to the conclusion that it is some characteristic of the brake lining which causes squeak, and that the only final solution to the problem is to get a brake lining which has not this undesirable characteristic We notice that in the clutch field resort to special facings is being made for freedom from judders, which is a kindred complaint. | ||