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).
Adoption of Girling brake systems and methods to improve chassis rigidity to reduce oscillation.
| Identifier | ExFiles\Box 120\3\ scan0065 | |
| Date | 15th November 1933 | |
| - 2 - E.3/HP.15.11.33. intention is to make up a trial set from pieces which were available and could be purchased. Thirdly we have adopted the Girling brake scheme as a possible mechanical alternative to the hydraulic system, as we consider it does offer some outstanding advantages but whether we think all of it is good and applicable for our purpose we have yet to decide. A further claim for the Girling is elimination of brake squeaks and this also we are investigating. The aforegoing gives a brief resume of what we are doing to improve the distribution part of the brake gear, the Girling scheme being part of the programme, and we should be glad to know if you approve of the policy outlined. With reference to the second part of your memo, may I refer you to our letter of yesterdays date E.3/HP.14.11.33 dealing with the design of the spectreCodename for Phantom III. In this design we have laid down a frame which has a very high degree of torsional rigidity and we believe that this is primarily the way to eliminate front end oscillation irrespective of the design of front axle employed. In any new chassis work we propose to follow these same principles, and we believe it will give the result we desire without the use of friction damped weights on the front dumb irons. A good example of a stiff frame with the front end entirely free from oscillation is found in the 8 cylinder Terraplane of which we have had recent experience. On our existing chassis, bonnet and radiator movement has to a large extent been reduced by the use of the centrally mounted radiator but this movement is a variable which appears to be very dependent on the type of coachwork fitted so that now and again we get a car on which the oscillation is more pronounced than usual. No doubt in such cases a bumper bar fitted with friction damped weights might be of benefit, and I would certainly agree that it would be worth our while to rig up and test such a scheme. As an alternative cure however, since we are using dashboards of deep cast design which possess a fair share of rigidity it occurs to me that we might steady the radiator from the dash by suitable stays provided the radiator suspension were given enough latitude to accommodate the movement of the frame. With such a scheme the front bonnet clips would probably have to put up with more movement than they do at | ||