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).
Letter to the Adamant Engineering Co. Ltd. regarding the heavy steering of an L.7 Type Steering Gear and requesting modifications.
| Identifier | ExFiles\Box 28\3\ Scan033 | |
| Date | 31th October 1934 | |
| 84094 Expl. Dept. Hs{Lord Ernest Hives - Chair}/Hdy.{William Hardy}5/MJ. 31st. October, 1934. The Adamant Engineering Co. Ltd., Dallow Road, Luton. Dear Sirs, For the attention of Comdr. Matravers. We have just given your L.7 Type Steering Gear a short trial on the road and find that, owing to the relatively low mechanical efficiency in comparison with our own gears, the steering of the car is unduly heavy. At present the layout of the steering is such that from lock to lock corresponds to 2.46 turns of the steering wheel. This is identical to our Standard layout. We wish to make the steering of the car lighter by increasing the lock to lock turns of the wheel to 3.25 but are unable to do this by shortening the pendulum lever as the full travel of your gear gives only 2.75 turns of the wheel. We were wondering whether, by slight modification to the existing L.7 gear, it would be possible to increase the travel of the Pendulum shaft sufficiently to give the desired figure of 3.25 turns of the wheel and so enable us to fit a shorter pendulum lever. Will you please let us know whether you think the above can be done or whether it will be necessary to have a cam of less helix angle. If a new cam is required, have you one in stock that would suit our purpose. We are aware that the efficiency of your gear may increase as it becomes run in but we doubt whether it will reach the figure for our own gears which is 85 - 90%. Even assuming that your gear does attain this efficiency we should still wish to try a lower gear. In our letter of the 15th. Oct. we mentioned that we were going to "run in" the L.7 gear on a rig. Unfortunately we were unable to do this so that we have not obtained any figures for the efficiency in the run in condition. We should be very glad if you would give us any figures you have obtained giving a comparison between the new and "run in" conditions. Yours faithfully, | ||