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).
Redesign of the earth contact plug for front hubs on various car models.
| Identifier | ExFiles\Box 63\2\ scan0311 | |
| Date | 1st June 1937 | |
| 6153 By Copy to Mr. [illegible] Rm.{William Robotham - Chief Engineer} WHC. HIVES. Platt/RM.{William Robotham - Chief Engineer} WST E/EV.{Ivan Evernden - coachwork}6/M.1.6.37. EARTH CONTACT IN FRONT HUBS - N.SCH.4903. The type of plug in the end of the stub axle shown on N.Sch.4903 calls for a fine limit between the plug and the bore in the stub axle. To overcome this difficulty we have re-designed the plug to give it elasticity on the revised design shown on N.Sch.5156 herewith. In the case of the existing Ph.III. and 25/30 cars, we have to take note of the fact that the limits on the bore in the stub axle are ±.01. We have, therefore, suggested that until we can reduce this limit to ±3, the hole be reamed to .5156 +.003 and oversize plugs be provided. In the case of the Bentley, the present centre bore is too small and has to be enlarged, therefore, the difficulty does not arise. It would appear, therefore, that we have to have two sizes of plugs for the Ph.III. and 25/30 cars to cover existing and future production respectively, whilst one plug each will deal with the Bentley and the Wraith III. E/EV.{Ivan Evernden - coachwork} Att: N.Sch.5156. | ||