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).
Modifications and testing procedures for Girling wedge units and the servo system.
| Identifier | ExFiles\Box 174\3\ img204 | |
| Date | 16th February 1940 | |
| (2) Girling Wedge Units. Two sets of wedge units to have the plungers and wedges ground down 0.001 and chromium plated 0.0005 thick. To be fitted to 9. and 11 B.V. Cost of this operation on a production basis, to be ascertained from New Hudson's. Snap on covers to be fitted to keep dust away from inner end of wedges on all chassis as on hydraulic wedge units. The cover should preferably be a smaller size than the one used on hydraulic units so that existing wedge unit housings can be modified to take these covers. If a simple arrangement to prevent dust reaching the outer end of mechanical front wedges can be devised without alteration to existing parts this should be fitted to 8. and 9.B.V. (3) Servo. As it appears to be impossible to prevent water entering the servo under extreme conditions, as when submerged in water splash or surrounded by packed snow, we should try the effect of a drain hole to let the water out. This should be tested on 2.B.50 in the form of a flat at the lowest point of the pressure plate in the "brakes off" position. A 0.500 diameter hole should also be put as high as possible in the pressure plate in an attempt to obtain some ventilation. The above modifications should be tested as follows:- (a) Deliberately put water in servo through upper vent hole and drive in road to determine how soon, in terms of miles, the servo can be dried out. - Continued - | ||