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).
Friction coefficient on propeller shaft splines for Hardy-Spicer and Phantom III shafts, and proposing further tests.
| Identifier | ExFiles\Box 94\4\ scan0131 | |
| Date | 29th October 1936 | |
| 337 (GRY.{Shadwell Grylls}) Did W. Bell do these tests? Rm{William Robotham - Chief Engineer} c. Rm.{William Robotham - Chief Engineer}-Ba. E/HDY.{William Hardy}1/HP.29.10.36. Propeller Shaft Splines. With regard to the difference in the coefficient of friction between the splines on the Hardy-Spicer and Phantom III shafts, .165 and .195 respectively, our previous tests on sliding joints have given coefficients varying from .190 to .250 more or less independent of the load on the splines, and not consistently higher or lower when hardened compared with unhardened. The Hardy-Spicer shaft has, therefore, given a considerably lower coefficient than we have so far obtained, but we are unable to see any reason why it should. We propose to ask for the test to be repeated on all the Hardy Spicer shafts we have in the works (at least three, I think). E/HDY.{William Hardy} | ||