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).
Gearbox noise, gear finishing processes using Brown & Sharpe cutters, and a comparison with Napier gearboxes.
| Identifier | ExFiles\Box 23\2\ Scan002 | |
| Date | 8th September 1909 | |
| Filed 5/10/09 Suggests / Brown & Sharp 8th September 1909. RS{Sir Henry Royce's Secretary}/D889 C.J. With reference to your sheet CJB/R2489 attached, undoubtedly the change in the gear is due to the small diameter and light plate clutch which is on this low powered car, also the small amount of power transmitted through the box would undoubtedly leave the box much more silent than if they were transmitting great horse power. If the gears are not improved by the use of the shaving machine and the altered proportions, we shall have to resort to finishing them with Brown & Sharpe cutters by the Brown & Sharpe process. As I have pointed out before, we have tried to avoid this system owing to commercial reasons, such as the difficulty of getting cutters from America. The other conclusion we have come to is that a great deal of harm is done with the grinding of the gears. I believe that Napiers do not now grind their gears together. Mr. Clarke was surprised to hear that the 15 H.P Napier box was good (these varied considerably), saying that it must have been a chance good one. He thought their 45 H.P. box was good and by far the best box Napier had made. There seems no reason why the 15 H.P. should be good, - from a designer's point of view, - but there are some reasons why it should get bad in shorter time than ours. I feel sure that it is their practice of finishing with Brown & Sharpe X437 | ||