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).
Analysis of crankshaft deflection, balance weights, and the use of copper-lead bearings with comparisons to competitors.
| Identifier | ExFiles\Box 173\4\ img228 | |
| Date | 5th December 1935 guessed | |
| -4- Supports at AA.{D. Abbot-Anderson} Load applied at aa{D. Abbot-Anderson} gives deflection a, applied at bb gives deflection b, at cc gives deflection c. Balance weights at AA{D. Abbot-Anderson} in the example shown us were 20° in front of the crankpin centre, and at BB were 40° in front. 20° AA{D. Abbot-Anderson} 40° BB The shafts do not appear to be in static balance, but they say run without deflection in the bearings. Packards use copper lead bearings on the connecting rods of the twelve, but not on the journals, which they say do not need them. Conn. rod bearing clearances .0015". I do not know how much notice we ought to take of the above, but Packards were emphatic about it. We were told that copper lead bearings must be bell mouthed cut on given clearance, to the extent of the crankshaft deflection. They say that there is less difficulty about running copper lead on an 8, because the 8 cylinder balance weights are about the same for each way of doing it. All American 12 cylinders have four bearing crankshafts, which in some cases might give flywheel roughness. I have a drawing of the 12 cylinder Packard crankshaft which they say weighs 120 lbs. Cadillacs say the amount of inertia in a rubber | ||