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).
Tests on various gears to diagnose and eliminate rattling and humming noises.
| Identifier | ExFiles\Box 75\1\ scan0048 | |
| Date | 5th February 1913 guessed | |
| -5- in the teeth, and if the shafts were run at certain critical speeds it would develop into a very violent periodic rattle. We then tried another set of standard Brown & Sharpe gears which had been scrapped by the Gear Box Dept. as being of no use and humming badly, and these were run in a similar way to the first test. These gears also did not improve. We next tried a pair of the same gears only soft, these improved very rapidly and although they were quite bad originally they were practically noiseless after being run in in this way ( we abandoned the coarse emery and used a very fine grinding paste and also ran the rig at a very slow speed to reduce as far as possible the chattering). The hum could only be just perceived in a standard chassis(with undershield etc.)by getting the ear quite close to the box. I concluded from these tests that the Brown & Sharpe cutters were really very badly out and decided to try some planer cut gears. During the above tests we had tried several degrees of braking and had ultimately abandoned the brake entirely. Also the rattle of the gears was so violent that it was obvious that no good result could be expected from the rig as then made, so I abandoned the scheme of attaching the flywheels rigidly to the shafts and | ||