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).
Humber's experience with cyanide hardened gears and a proposal for testing a Humber gearbox with a Rolls-Royce engine.
Identifier | ExFiles\Box 112\2\ scan0036 | |
Date | 15th September 1937 | |
-2- Rm{William Robotham - Chief Engineer}/Gry{Shadwell Grylls}/R.15.9.37. When Humbers first went to cyanide hardened gears they had a lot of trouble with noise, and state that a careful check has to be kept on the material of the gear blanks and on the accuracy of the temperature of the cyanide furnace. Solid gears were said to give better results than panel gears. These three points have to be checked in order to avoid distortion. They say that they keep the lead of the gears within .002, which we can hardly believe. As we are seriously contemplating omitting tooth grinding on the Phoenix gearbox and adopting cyanide hardening, we recommend buying a Humber gearbox, fitting it to a 25/30 car so as to get an impression of the silence in conjunction with a Rolls-Royce engine, and finally running it to destruction on the dynamometer. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} | ||