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).
Suggested experiment to modify the Phantom II steering nuts to improve performance.
| Identifier | ExFiles\Box 17\4\ Scan052 | |
| Date | 28th June 1933 | |
| GRY{Shadwell Grylls} X7430 To BY.{R.W. Bailey - Chief Engineer} from Da.{Bernard Day - Chassis Design} Da.{Bernard Day - Chassis Design}1/HP.28.6.33. c. for E.{Mr Elliott - Chief Engineer} Hs.{Lord Ernest Hives - Chair} Phantom 2 Steering. -------------------- Herewith is N. Sch. 3759, sketch of the suggested experiment of reducing the area of the steering nuts so as to enable the oil film to be cut through by a sharp and heavy load on the pendulum lever. The area to load in either direction provided by these new nuts is approximately 1/10th of the existing area. As wear may occur an adjustment is provided. To avoid sticking in parking the angle of the thread has been increased approximately 2°; this has been done by reducing the pitch diameter of the worm retaining the lead unaltered, so that the leverage is unchanged, and an existing complete steering column and pendulum lever, with the exception of the new nut and worm only, can be used. Another way would have been to alter the pendulum lever and increase the angle of the rocker shaft, but it seems better to try the scheme which involves minimum alteration first. It is understood from Experimental Department that no difficulty is anticipated in grinding the hardened steel threads of the nuts, given suitable tackle, and that experimentally a thread can be machined with a finish equal to grinding. Da.{Bernard Day - Chassis Design} | ||