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 summarizing test results for ignition system components like contact screws, contact breakers, and condensers.
| Identifier | ExFiles\Box 61b\1\ scan0123 | |
| Date | 19th August 1930 guessed | |
| -3- (5) Domed contact screws. Doming the contact surface of the tungsten screw point, we recommend, should be standard practice. The bedding together of the points is helped and also the formation of a ledge or "new moon" on the surfaces where points have not been lined up accurately is considerable reduced. Doming does not improve the contact surface condition. (6) Tungsten contact points run with three lobe cam. The condition of these points after a 10,000 mile test was no better than standard, the screw point still being badly oxidized all over. (7) Lever with offset rubbing block to give sharper break. This did not improve the condition of the points at all. (8) Delco-Remy contact breaker with screw point support. Stiffened up. A 10,000 mile test was completed and at the conclusion of run the points were in poor condition bedding only on 75% of the surface and a deep cavity having formed on the lever point. There was complete absence of oxidation, however, on both points. Towards the end of the run misfiring occurred at slow speeds. (9) Lower value condenser. A 10,000 mile test with a condenser of .23 m.f. showed considerable reduction of oxidation on both points. Further tests on points with various capacities condensers are reported separately. | ||