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).
The high-speed endurance testing of special duralumin contact breaker levers for Watford magnetos.
| Identifier | ExFiles\Box 48\2\ Scan368 | |
| Date | 28th February 1928 | |
| X.8796. EFC. {E. Fowler Clarke - Electrical Engineer} WC.80. WATFORD CHASSIS MAGNETO CONTACT BREAKER. We have had some special duralumin contact breaker levers for test on standard Watford magnetos. The special feature of these levers is that the rubbing block is of deeper section and also riveted to the lever in a better way and reinforced by an additional small steel backing. This has been done to cure the trouble experienced in service of the rubbing block and lever fracturing where the former is riveted to the latter. We have now completed a high speed endurance test on one of these levers fitted to a standard EO6 magneto. The magneto was run at 3000 r.p.m. for 160 hours on the bench after which it ran for a further 15 hours at 4000 r.p.m. The primary gap measured before the run was .012" and after the run .005", showing that allowing for the wear of the contact points the rubbing block wear was considerable. No trouble was experienced during the test and an examination of the lever afterwards shewed it to be quite O.K. The lever is handed to you herewith for inspection. Another of these levers is running on a standard magneto on 8-EX. EFC {E. Fowler Clarke - Electrical Engineer} /H.E.West. | ||