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).
Production, hardness, and quality control of steering cams for the Wraith model.
| Identifier | ExFiles\Box 9\7\ 07-page178 | |
| Date | 11th November 1938 | |
| 650 also 1300 To RHC.{R. H. Coverley - Production Engineer} from Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. By.{R.W. Bailey - Chief Engineer} Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}4/MH.{M. Huckerby}11.11.38. STEERING CAMS. We assume that you will soon be producing Wraith steering cams on the new Fellows machine. This machine appears to produce very accurate cams and we do not anticipate that there will be any trouble due to errors of form. We do think, however, that we should be careful to maintain the hardness and depth of case as faults in this respect may only show up after one or two years' service. It is quite conceivable that the Adamant Co. have consistently produced cams with harder or deeper cases than the drawing calls for and, as it is essential that we at least maintain their standards in these respects, we recommend that you should measure the hardness and depth of case on the worm track and bearing cones of at least three Adamant cams. Similar measurements should be taken on three of our first batch of cams and on one from each subsequent batch to be hardened until we are sure that the hardening is above reproach. We propose to give you a cam which has satisfactorily completed a large mileage (14,700) on one of our experimental cars and we suggest that this should be one of the three Adamant samples. If you adopt the process of finish cutting the worm tracks after carburising and before hardening we suggest that care should be taken that the amount of metal removed should not be allowed to increase over that removed on the original samples as this, of course, reduces the thickness of the case. Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} | ||