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).
3rd gear and flywheel vibration analysis.
| Identifier | ExFiles\Box 14\2\ Scan058 | |
| Date | 1st November 1929 | |
| Hs{Lord Ernest Hives - Chair}/Tans/ADS.11.29 contd. -7- 3rd Gear. 32 - 35 period now at approx. 28 m.p.h. 40 - 43 " " 36 m.p.h. 48 - 55 vibration smoother. There was a bad rattling vibration at 60 m.p.h. now instead of 65 m.p.h. (2) Visual observation of flywheel vibration. Purely by chance we found that when running up an engine in a chassis with the gear box off and the clutch dismantled (leaving only the flywheel plate on the crankshaft as before) vibration of the flywheel could actually be seen. The flywheel became indistinct at various speeds, and vibrations could be felt through the chassis. With the Rotoscope, the flywheel appeared to be "flapping" or vibrating about a diameter while rotating. This commenced at about 2300 R.P.M. and at 2800 R.P.M. it appeared to have an amplitude at the rim of no less than .125" approx. We reassembled the rest of the flywheel and clutch plates, and then we found that the vibration appeared reduced in amplitude and frequency, to approx. .040" and 3500 R.P.M. respectively. We could now run through the vibration period. By holding a finger against the rear projecting spigot on the clutch, we could pick out the period. | ||