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).
Steering pivot failures during frame bumping tests and a conclusion on their safety.
| Identifier | ExFiles\Box 2\12\ B002_X168-page191 | |
| Date | 5th December 1913 | |
| From Exp. Dept. Copies for: J.{Mr Johnson W.M.} R.{Sir Henry Royce} Da.{Bernard Day - Chassis Design} Ha. Wor{Arthur Wormald - General Works Manager}/Hys/L51213. December 5th. 1913. Re Steering Pivots. X.168. Recently we have been running on the frame bumping test pivots F.3372/3 and F.3697/8. These pivots are similar except that the former are a little longer than the latter in the stub. The section of the U and the root of the stub are exactly the same. F.3697/8 are the actual pivot now being used on 2700 and 2900 series cars. Previous to using these pivots on the bumping test only two pivots had been broken during the tests of many frames, and these were of the type which were until recently standard (F.3253). Since using the present type of pivot however, we have broken no less than 4 as follows :- 1. F.3372 - Off side broke in 6 hours 3 minutes. 1. F.3697 - " " " " 7 " 25 " 1. F.3697 - " " " " 12 " 47 " 1. F.3698 - Near " " " 15 " 32 " In each one the breakage was exactly the same, that is, the stub broke away from the U section with a clean fracture just where the small radius starts. Judging from the frequency of these failures I do not think it wise that this type of pivot, in its present form is absolutely safe to | ||