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).
Dynamometer testing of gears and an inspection of the propeller shaft after a road test.
| Identifier | ExFiles\Box 92\5\ scan0037 | |
| Date | 31th October 1935 | |
| -3- After the original failures we fitted 25° gears and had no trouble on the road during 10 months' running. New gears were fitted for this dynamometer test and have proved themselves adequate. This appears to prove that individual tooth strength is the important factor and not the strength of the total number in contact. As these gears are not ground they are not good as regards silence, but show that the original J-111 box which is 10 lbs. lighter than the SpectreCodename for Phantom III box is large enough for the SpectreCodename for Phantom III car even when the torque is 20% higher than now. The first speed gears were .925 wide and made of S2NCR material, the pinion being .020" large at the pitch line and the wheel .020" small. The surface of the pinion failed due, we think, to foreign matter, and several of the wheel teeth are cracked. This gear required a huge force to keep it in mesh, which was done by locking the lever in the gate. Owing to flexibility of the operating pieces the gear did not run fully in mesh, and the wheel teeth were cracked on the engagement side. (Oil used 50/50 Hi-Press and O.W.) Propellor Shaft. To prevent excessive angularity of the joints the axle was fitted with a torque member rigidly fixed at the front end. The joints were in perfect condition after the test. HS{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} | ||