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).
Secret memo discussing the design, loads, and stresses for a rear axle project named 'Rippletto'.
| Identifier | ExFiles\Box 114\1\ scan0252 | |
| Date | 1st November 1939 | |
| 1015 + 1022 SECRET. To Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} from Ev.{Ivan Evernden - coachwork} c. to Rm.{William Robotham - Chief Engineer} c. to Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} Ev.{Ivan Evernden - coachwork}7/JH.1.11.39. re Rear Axle - Rippletto. On Pl.29 herewith we shew the Salisbury rear axle with 7.000 ring gear, and suitable lengthened but standard design of axle tubes. We use the Salisbury spring seat, and standard B.V. rear springs of the correct load, in which case a packing of approx. .250 ins is required, and special strap bolts. The brake equaliser support goes on a facing on the existing axle casing. The axle centre box is that shewn on makers drawings HA-001-6 and HA-001-2 and HA-00-5. We want the 4.88 to 1 ratio. On Pl.29. we have shewn the estimated loads and for our own edification we have taken out some of the more important stresses. (see appendix). According to the loads and stresses given by the makers for this size of axle our figures do not lead us to believe the project to be impossible. We shew three possible steel wheels - 1 - B.V. std. - overhang on bearing 1.862". 2 - B.V. Light 4" rim " " 2.062". 3 - Final Rippletto wheel " " 1.612". Stresses are given for the worst case, but we definitely need the new centre to give the final Rippletto wheel, for - Rippletto with Salisbury axle. Rippletto with B.V. axle. Ripplet with B.V. axle. Myth with Salisbury Axle. Myth with new R.R. axb. EV.{Ivan Evernden - coachwork} | ||