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).
Experiments with battery ignition contact points, focusing on scrubbing action and various methods of bedding for tungsten points.
| Identifier | ExFiles\Box 35\6\ scan 305 | |
| Date | 26th August 1927 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. BY.{R.W. Bailey - Chief Engineer} c. Wor.{Arthur Wormald - General Works Manager} X2894 EPCL/T26.8.27. Y4652 BATTERY IGNITION CONTACT POINTS. Further to our EPCL/LGl4.7.27 and dealing with the various experiments in the order there listed :- No.27. Scrubbing action for tungsten points with alternative springing - to L.ec.2422. The points in this experiment were flat, but the experiment was started not specially bedded. The damper was in position. Although no attention was required, the condition of the points at the end of the test was very much like other tungsten point experiments which we have conducted. Sample point labelled 27b. As a result of this and another recent test described below, we recently decided that we should make a definite distinction between points carefully bedded initially, and points not bedded initially, and only work with the two extremes, i.e. the one extreme case will consist of initial bedding to make contact all over, or nearly so, and the other, of points bedding on the edge only, or domed points bedding initially on a small circle (special setting not performed). Still more recently, we have decided that for the time being we must work only with accurately bedded points until we get a good result. N.B. the accurate bedding which we should make on these experiments would be considered to be out of the question on production or re-fitting of contact breaker points. further Further, previous to giving the actual details of the experiments, we may say that we have now practically proved that accurate bedding of points gives scarcely any better results on our own ignition, this referring more particularly to platinum. Also that incorrectly bedded points. e.g. starting | ||