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).
Experiments to mitigate chassis 'Jellying' through shock damper loading and altering frame periodicity.
| Identifier | ExFiles\Box 28\5\ Scan011 | |
| Date | 19th February 1930 guessed | |
| -4- to the axle. Thus a bare chassis is practically immune from "Jellying". When a body is fitted the periodicity of the frame is altered, in almost every case to the detriment of the steering and radiator steadiness. (7) Effect of Shock Damper Loading. The hydraulic dampers control the axle as far as the frame will allow. If their loading is progressively increased, up to a point "Jellying" is decreased until a state is reached where the damping is so great that the frame starts to move excessively and with further increase in load "Jellying" actually becomes worse. The standard loading is at present about as much as can usefully be employed and is successful in preventing high speed wobbles building up. If the shock dampers are made single acting matters are not improved very much, whilst the riding of the car suffers. In the light of this information we made the following successful experiments :- Altering Frame Periodicity. (a) We fastened a bar across the front dumb irons and to the extremities, 58" apart (in line with centre of road wheels) fitted two weights of 1 cwt. each. This shewed itself to be 90% cure in both our tests. (b) As a parallel experiment we tried with and without front wings. The removal of the front wings made the "Jellying decidedly worse. | ||