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).
The difficulty with a larger experimental worm of .900 pitch steering component.
| Identifier | ExFiles\Box 68\1\ scan0003 | |
| Date | 7th January 1928 | |
| Hs.{Lord Ernest Hives - Chair} BY DA{Bernard Day - Chassis Design}/HDY.{William Hardy} c. to BJ. Wor.{Arthur Wormald - General Works Manager} R7/M1 7.1.28. DIFFICULTY WITH LARGER EXPERIMENTAL X. 8430 WORM OF .900 PITCH. X. 7430 I cannot understand why this should be so, because the angle of the worm threads is less liable to give irreversibility than the .720. The object of the .900 larger diameter was to give less end thrust for a given effort on the road wheels, and greater area of oil film to carry this reduced load. EAC. 7. is now the best steering we have ever known (shorter pendulum lever) - (Dodd's report) on these most trying roads - rough surfaces, also an extra-ordinary number of sharp dangerous turns. R.{Sir Henry Royce} | ||