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).
Proposal for a simplified steering tube adjustment for the Wraith II and P3 chassis.
| Identifier | ExFiles\Box 9\7\ 07-page018 | |
| Date | 18th November 1936 | |
| F.J.H 10664 650 To: [REDACTED] from REC. c. to Rm.{William Robotham - Chief Engineer} RHC.{R. H. Coverley - Production Engineer}2/CB.18.11.36. WRAITH II STEERING TUBE ADJUSTMENT. We attach hereto BP. Ex.25145, showing a simplified form of steering tube adjustment, suitable for application to Wraith II and P3 chassis. It will be seen that the end of the tube is turned and screwed, thus deleting the separate pegged and brazed sleeve shown on LEC.6351. The thread however, is only used as a form of adjustment, and is not subject to end thrust or bending loads these being taken by the friction on the parallel fitting portion. A model of this construction, but having the screwed portion of the tube removed, (i.e. relying solely on the contraction of the ¾" dia bolt) has been tested and found to withstand a tensile load of 3,600 lbs. before slipping occurs, thus providing a factor of safety of 4:1 by friction alone. The saving in factory cost of this scheme, as compared with LEC.6351, would be about 9/6d. per chassis, which represents £700 p.w. on an assumed weekly output of 20 Wraith to 10 Phantom III chassis. REC. [Illegible signature] | ||