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).
Letter to The Gleason Works discussing rear axle gear scoring during testing.
| Identifier | ExFiles\Box 111\4\ scan0065 | |
| Date | 12th September 1938 | |
| 302 Experimental Dept. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}5/MH.{M. Huckerby} 12th. September 1938. The Gleason Works, 1,000 University Avenue, Rochester, N.Y., U.S.A. Dear Sirs, Replying to your cable; herewith arrangement print of the rear axle in question. We have marked on it the torque on the pinion on the various gears. The scored pair of gears, which we have sent for your inspection, have run 30 hours on third followed by 70 hours on top, followed by 20 hours on 2nd. gear. The scoring has become progressively worse. The lubricant used was Vacuum Mobiloil HGL. It was maintained at 90°C during the tests. A second pair of gears whose hardness we checked at the request of your Mr.Ward, who is now in England, and which were about Rockwell 64, have been run for 30 hours on 3rd. gear using oil just delivered by the Vacuum Co. show incipient score lines. We wonder whether a smaller pinion spiral angle would not be an improvement. Yours faithfully, for ROLLS-ROYCE LTD. | ||