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).
Adaptation of a Humber Snipe crankshaft damper to a Bentley 40 engine to investigate a vibration issue.
| Identifier | ExFiles\Box 126\2\ scan0193 | |
| Date | 11th June 1941 | |
| C.T.S. How much to make? Rm{William Robotham - Chief Engineer} To [strikethrough]Ev.{Ivan Evernden - coachwork}[/strikethrough] from Rm{William Robotham - Chief Engineer}/HH. c. to Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}/HH.2/SW.11.6.41. We send you herewith blueprint of PL.681 - Humber Snipe Type Crankshaft Damper - Bentley 40. This scheme has been produced in accordance with a request by Rm.{William Robotham - Chief Engineer} to ascertain the cause of a vibration appearing in the engine at approximately 50 MPH. This has been put down to two theories :- (1) The Exhaust - which is being modifed. and, (2) A crankshaft vibration. In order that we may prove a crankshaft vibration, we adapted the Humber Damper to this crankshaft. The inertia of the damper centre is considerable, and not a desirable feature. The damper springs will probably require some modification to modify the slipping torque, this will be found by experiment. In any case, we are bound to learn some characteristics of the crankshaft with this damper fitted. Rm{William Robotham - Chief Engineer}/HH. | ||