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).
The unreliability of present rear springs compared to pre-War models, recommending a return to the old type.
| Identifier | ExFiles\Box 43\2\ Scan008 | |
| Date | 12th April 1920 | |
| Contd. -2- Hs{Lord Ernest Hives - Chair}3/LG12.4.20. The results of the bump test show conclusively that the present rear springs which we are fitting are very much less reliable than those we fitted previous to the War. Even if we have the solid bottom leaf they will still be less reliable than the old rear springs. We think that the stresses in the present springs are worse than was anticipated owing to the fact that the curvature of the plates not being to the specifications. X.3910. The rear spring which broke on the latest type car in Spain had broken at the bottom leaf in a similar place to where they break on the bump rig. We feel we ought to take urgent steps to revert to the old type springs. We have three faults with the present springs which did not exist on the old type springs. - 1. Possibility of breakages. 2. Leaves squeaking. 3. Need of extra friction. X.3900. We feel certain that when cars with the thick leaf rear springs get into general use on the Continent and In America there will be a number of cases of broken leaves. At present we have a main at the works from the Service Depot at New York and he reports that they get a great number of the top leaf on the front springs breaking. That being the case they are practically certain to have a number of the latest rear springs break. The bump test records show the front springs to be stronger than the thick rear springs. We recommend that we should cable America to prevent them ordering any of the thick leaf rear springs for the American cars. | ||