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).
Page of typed fitting instructions for a spring assembly, with an accompanying blueprint diagram showing part numbers and notes.
| Identifier | ExFiles\Box 68\1\ scan0146 | |
| Date | 7th July 1926 guessed | |
| -2- contd :- unacquainted with the job should consider .188 as applying to all springs and fit them accordingly. This would mean that the static load on the ball end with 2520 lbs. springs would be only 130 lbs. instead of 300 lbs. However, even if the correct amount of required set up is known, small errors in fitting will produce large differences in ball end load, owing to the tremendously high rating and small diameter of the springs employed. As an example, suppose the 3500 lbs. springs to be fitted with .160" initial set up instead of .188" (it is not easy to measure this set up accurately), and the 2500 lbs. spring with .280" instead of .250" static deflection. contd :- [Blueprint Text] Part Numbers & Dimensions: F.5007 4575 F.9876 2.500 E.17476 .425 1.450 COMPRESSED 1.25 E.9771-5 K.5003 F.9874 K.4627 F4968 F6965 F.9875 Notes: EVERY NEW SS{S. Smith} SPRING SHOULD HAVE DISTANCE X REQUIRED WHEN FITTING SPECIFIED NOTE. IF PLUG F4968 PROJECTS FROM TUBE F4613 BY AN AMOUNT LESS THAN .188 WHEN SPRINGS ARE FREE, USE WASHER F9843 SWEATED IN POSITION AS SHOWN. | ||