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).
Cause of 'front wing dither' on Bentley cars, attributing it to body rigidity rather than the wing and running board design.
| Identifier | ExFiles\Box 3\6\ 06-page221 | |
| Date | 31th August 1934 | |
| X4513 Other correspondence in X.4013 (Paris Trials Car) & X.4533a (10,000 mile Tests [Handwritten initials: Rm{William Robotham - Chief Engineer}] Copy to [REDACTED] Hs.{Lord Ernest Hives - Chair} Mr [REDACTED] RWR/IB.31.8.34. Re:- BENTLEY - Front Wing Dither. We have read the memo from Chateroux from CWH and RWRB/MR.24.8.34. concerning the Front wing dither on Bentley, and we have discussed the suggestions therein with Hs{Lord Ernest Hives - Chair}/Hm.{Capt. W. Hallam - Head Repairs} It is agreed that there is every reason to believe that the front wings and running board being in one piece has nothing to do with the front wing dither. The reason why such cars do not dither in the front is because they have open bodies which have no torsional rigidity. all the cars mentioned with this particular wing and step in one are Van den Plas open-bodied cars. In the days of open bodies on the Phantom we demonstrated this fact. We are strongly opposed to any recommendations being sent to Coachbuilders to fit these wings without further evidence to contradict our past experience. On open cars they stand up without cracking because there is no dither, but fitted to a Saloon the dither would soon crack them. That this would happen is indicated by the fact that unless we attach the rear of the front wing very flexibly to the running board, the wing tears itself away from the running board attachment. We understand that you have [handwritten: Justin?] inspected a pair of these wings and running board in one to be fitted to a Park Ward Saloon. The experiment is of interest, but we suggest that the car should be looked upon as an experimental car and the scheme should not be put into production until at least 10,000 miles has been covered under Continental conditions. The whole subject of front end dither is being investigated by Hs{Lord Ernest Hives - Chair}/Hm{Capt. W. Hallam - Head Repairs} in conjunction with ourselves, both with a view to doing something to improve the chassis as it is at present and to determine an improved frame in future. The tests are being confined to closed cars and one of the things being tried is a wing and running board in one unit to confirm our previous experience and deductions. EV.{Ivan Evernden - coachwork} | ||