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).
American chassis, detailing observations on its gears, admirable features, and engine performance.
| Identifier | ExFiles\Box 72\2\ scan0085 | |
| Date | 22th July 1928 | |
| To CJ. from R.{Sir Henry Royce} c. to BJ. BY.{R.W. Bailey - Chief Engineer} c. to Hs.{Lord Ernest Hives - Chair} Hy.{Tom Haldenby - Plant Engineer} c. to OY. Wor.{Arthur Wormald - General Works Manager} AMERICAN CHASSIS. I send herewith a few remarks about the chassis sent to WW. for inspection. (1) GEARS. Various people have reported that the engine gears and the gearbox gears are more noisy than we pass in England. I distinctly dislike the system of 'Rounding the teeth' so that in changing the gears feel extremely harsh, and grab one another, unless very skillfully synchronised. I was surprised to find how difficult it was to change gear, and positively made more liable to damage by the grabbing teeth and sharp corners. ENGLISH. AMERICAN. (2) ADMIRABLE FEATURES. Two items called for admiration. (a) The first is that the drop forgings are much lighter and nearer to size than we obtain in England, and they are cleaner and better finished. It would seem as if in American these forgings were bought by the piece, and under strict inspection, whereas we may buy them by the pound, and we do not have a sufficiently strict limit on the weight. (b) The other item is road springs. These are superior to what we are getting in England in finish, though the clips are not so numerous or effective. (They seem to be of the original old pattern.) The spring leaves however are slightly greater in number, and the top leaf is thinner points we think add to the life of the spring, and also what seems still more important, each leaf seems to be efficiently ground to an even thickness throughout their length. DA.{Bernard Day - Chassis Design} says that the want of uniformity of thickness in our springs shews in calculation to materially affect the life of the spring, so that it is well worth the cost and trouble of properly grinding the whole surface of the plates, and to a uniform thickness. We can see no reason why this should not be done without very much expense, as the process could be automatic. (3) ENGINE. 40 m.p.h. Hs.{Lord Ernest Hives - Chair} thinks (I don't agree) this is not due to crankshaft torsional period, but is due to something out to balance, setting up a synchronous vibration, and this he will investigate and report. contd..- | ||