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).
Method for grinding the Marles steering box worm to standardise it for 20/25, Spectre, and Wraith chassis.
| Identifier | ExFiles\Box 28\3\ Scan147 | |
| Date | 17th April 1935 | |
| X1300 RM{William Robotham - Chief Engineer} To Ws. from E.{Mr Elliott - Chief Engineer} E.11/HP.17.4.35. c. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. Mr Wakefield. re Grinding Marles Steering Box Worm. As the intention is to standardise the Marles type of steering at an early date on the 20/25 chassis, and as this type of steering will also be used on the SpectreCodename for Phantom III and Wraith chassis, it is desired to go into the question of producing the Marles worm. The samples we obtained from outside, from the Adamant Engineering Co. are only milled and somewhat imperfect in form. We should like to know if you can grind the desired thread form by using a grinding wheel of the same shape and diameter as the roller on the pendulum shaft arm, possibly pneumatically driven. A sample of the Marles worm can be obtained from the Experimental Department. E.{Mr Elliott - Chief Engineer} | ||