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).
Frame stiffness resonance and the pros and cons of using a cast dash.
| Identifier | ExFiles\Box 55\4\ Scan326 | |
| Date | 11th March 1929 guessed | |
| contd :- -2- frame stiffness. We have found out that in certain circumstances, to stiffen the frame torsionally is suicidal as it brings the frame period into the region of the front axle criss-cross period and resonance occurs at the critical speed, with most distressing results as the front end of the frame oscillates violently. (4) For gear work and high speed work the increased smoothness of the engine is most marked. Torque re-action is not appreciably affected. Cast dash. (1) Noise in body. We should not say that the cast dash was any advantage in this respect. The rubber connection between the dash and the scuttle should not be too solid or torque reaction is emphasised, nor too flexible or scuttle jellying is likely to occur. (2) The cast dash is a big improvement in making the steering column rigid. (3) The cast dash is somewhat heavier than sheet metal, the amount depending on the excellence of the casting. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||