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).
Reporting on comparative tests of various rear spring designs.
| Identifier | ExFiles\Box 80\2\ scan0186 | |
| Date | 31th July 1920 | |
| R.R. 255a (100 T) (S.G. 643. 19-2-20) G.{Mr Griffiths - Chief Accountant / Mr Gnapp} 2618 To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. c. to Bn.{W.O. Bentley / Mr Barrington} c. to E.{Mr Elliott - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} c. to By.{R.W. Bailey - Chief Engineer} X2628b Hsl/LG31.7.20. X.2628b. RE REAR SPRINGS. X.3981. We have carried out comparative tests on the bump test rig with - 1. Pre-war type rear springs. 2. Present type rear springs - sheared end without nibs and slots - solid bottom leaf. 3. Improved rear springs (n, sch. 363) parallel leaves - tapering in thickness - no nibs and slots. The results of these tests are attached herewith. It will be seen from the results of the tests that the pre-war type of spring is undoubtedly the most reliable as regards strength. The latest modification to our springs (No.3) has not shown up very well on the bump test. It is worse than the present sheared-end spring. We have lately been taking brinell tests of all the springs which we have borken. Although the results show a tendency for the leaves with the lower brinell figure to break more readily, the results are by no means consistent. We have been running the modified rear springs (No3 on two cars. We find on both of these cars that we still have trouble with the leaves squeaking. The trouble we believe, is less than with the present standard springs but there is no doubt it still exists enough to cause complaints. The results of our tests so far show that our pre-war spring is the best as regards strength and is the best as Contd. | ||