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).
Clutch design improvements, manufacturing specifications, and test results for the Phantom III clutch.
| Identifier | ExFiles\Box 85\2\ scan0292 | |
| Date | 16th November 1936 | |
| -3- Rm{William Robotham - Chief Engineer}/Smth.39/Ar.16.11.36. B. & B. say that they find in America that wide facings are good for judder. This is partially confirmed by the success of the original Long plate on 35-EX. We are trying a clutch with facings ¾" wider. The new clutch to be produced by the Design Dept. will have central splines of larger diameter, to obviate the tendency to bind during take up. (c) Manufacture and Fitting. There are several points to be watched to get the smoothest possible clutch. (1) Finish of flywheel and pressure plate should be smooth. (2) Pressure plate should not be more than .002 out of flat. (3) Fingers should be set with gauge to ensure parallelism of pressure plate and flywheel. (4) Clearance between lugs of pressure plate and cover slots should not be less than on drawing. (5) The thickness of the driven plate should not vary by more than .005 (6) The contact faces of the fingers and adjusting screws should be smooth. (7) The needle bearings of the operating cross shaft should be free. (8) There should be no play in the ends of the gearbox and engine tie links. (d) General. To get a line on why the Phantom III. clutch is so difficult to make smooth we have done the following tests:- (1) Mounted gearbox solid - no effect. (2) Tried prop. shaft damper - no effect. (3) Tried roller bearing sliding joint in prop. shaft - no effect. (4) Fitted control on rear axle to prevent twisting on springs - no effect. continued | ||