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).
The manufacture of trial springs for a Wraith III, detailing specific dimensions.
| Identifier | ExFiles\Box 10\3\ 03-page117 | |
| Date | 11th February 1938 | |
| 654 To HPS.{Horace Percy Smith - Experimental Factory Mgr} from Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}12/AP.11.2.38 WRAITH III. Will you please make springs to the following specification for trial in regard to trouble recently experienced getting the adequate slipping poundage. Free length - 1.050 wire S/CV. 13.SWG. - .092 Mean coil dia - .400 6 1/2 working coils. 1 each end ground square making a total of 8 1/2. Load at compressed length of .8 - 53 Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell} | ||