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).
Internal memorandum detailing experiments on Bentley floorboards to reduce booming noise in saloon cars.
| Identifier | ExFiles\Box 117\1\ scan0019 | |
| Date | 15th November 1933 | |
| To E.{Mr Elliott - Chief Engineer} from Ha/Rm.{William Robotham - Chief Engineer} C. Rg.{Mr Rowledge} Wor.{Arthur Wormald - General Works Manager} C. Hy.{Tom Haldenby - Plant Engineer} Er. C. Mx.{John H Maddocks - Chief Proving Officer} HHc. BENTLEY FLOORBOARDS. Referring to E.7/KF.15.11.33. We have recently been carrying out some experiments on booms in Bentley saloon cars. We have proved in the only two cases we have so far investigated, that the floorboards have a very considerable influence on this phenomenon. On our Expl. Bentley saloon we were able to reduce the booming by 75% by isolating the floorboards from the frame, and from each other, with sorbo rubber. We think it is also advantageous to isolate the holding down bolts from the floorboards, by the same sort of scheme we are at present using on the semi isolation bolts passing through the dashboard. We confirmed our results on the trials car Bentley saloon which was recently at the works after 5000 miles running. The necessity for experimental work on this subject was brought home to us when we tried the present 20/25 demonstration limousine on Monday last. The boom in this car is very similar to the one we have cured on the Bentley, and may possibly be susceptible to the same treatment. We appreciate that the feature we mention is only one source of booms, which can also be due to many other features of the coachwork, but in the case of the Bentley we do control the manufacture and supply of the floorboards which cause the trouble, and we know of no single alteration to the car which could improve it so much from the drivers point of view for so little cost. Though our experiments are incomplete, we raise this point now, so that this insulation can be considered with reference to the dies for the metal floorboards at present being designed. We have not yet run the experimental set of metal floorboards on the road, but hope to test them during the next few days. Ha/Rm.{William Robotham - Chief Engineer} | ||