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).
Stiffness of springs and axle clearance to avoid hitting the buffers.
| Identifier | ExFiles\Box 71\1\ scan0353 | |
| Date | 11th November 1927 | |
| Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} from DA.{Bernard Day - Chassis Design} c. to DA.{Bernard Day - Chassis Design} 48830 DA{Bernard Day - Chassis Design}1/M11.11.27. EAC.14 SPRINGING. X. 8410 X. 8830 X. 8840 With reference to hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}2/LG5.11.27., we do not think we can allow the axle to penetrate further into the frame than is shewn on N.schs. 2494/7., so that we think we must adhere whatever happens, to the dimension 5.8" from the top of the frame to the centre of the axle in the bump position. We gather from your hs{Lord Ernest Hives - Chair}/Rm{William Robotham - Chief Engineer}3/LG30.7.27., that you are actually experiencing trouble with hitting the buffers, and if this is so we suggest that the better plan will be to still further increase the stiffness of the springs rather than raise the car .250". We notice that the springs you are using are slightly less stiff than those we had asked for, namely, about 1%. This means a difference of nearly .1" and would be useful. We suggest however that we should go to 30%, and have indicated on N.sch.2503 herewith, in red, the spring we should like you to get. We may say that as we do not yet know the exact weight of the body we think a choice should be provided. We are aiming at 5 cwts. total body weight, but we do not know whether we shall get it. DA.{Bernard Day - Chassis Design} | ||