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).
Report discussing gear strength, pinion material, production difficulties, and the performance of cars in trials.
| Identifier | ExFiles\Box 49\2\ Scan170 | |
| Date | 31th October 1923 | |
| BY1-P31.10.23. contd. - 2 - gears is a sufficiently large increase to prevent recurrence of the trouble where the larger gears are fitted. The increase of strength is approximately 20%. We had no trouble with the original size gears in any of the cars run in France for the 10,000 miles trial, or since, although as a matter of fact, some of the cars which were run in the original trials are still running with the same gears, but since there appears to be nothing abnormal about the material of the Pinion which failed in Spain, it certainly looks as if even with the larger pitch of tooth we are running matters very fine. The use of the special low carbon case hardening type of air hardening steel which we use for the Rear Axle Shafts would cause real difficulty in the production of the gears themselves, in as much as the steel is difficult to cut and from that point of view would be likely to increase the cost of production considerably. We might find that with the present cutter heads it would not be a practicable proposition to cut this material, but in any case we have put in hand a number of Pinions with the object of trying out this proposal. In regard to the number of cars delivered with the original small pitch Bevel Gear is practically 400. BY | ||