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).
Testing alternative methods and materials for the battery ignition contact breaker on a 20/25 HP car.
| Identifier | ExFiles\Box 61b\1\ scan0188 | |
| Date | 19th January 1934 | |
| To BY.{R.W. Bailey - Chief Engineer} from E/Lid.{A. J. Lidsey} c. Hs.{Lord Ernest Hives - Chair} Sft.{Mr Swift} WHO. 86118. E/Lid.{A. J. Lidsey}1/HP.19.1.34. WST 10,000 Miles Test - 20/25 HP. Car. Battery Ignition Contact Breaker. On this car we should like to test out an alternative method of preventing ignition failure due to corrosion of the contact breaker arm pivot pin. On the Delco unit a brass pivot pin (138 Brinell) is used in conjunction with what appears to be a paper base (varnish) impregnated contact breaker arm bush. This method appears to be well worth trying out. We have previously experienced difficulties in fixing the brass pin into the distributor base by spinning, due to the pin cracking during the spinning over operation. We do not think, however, that these difficulties are insurmountable and we have asked Sft.{Mr Swift} to carry out some experiments on a standard distributor base using a brass pin of the same Brinell as the Delco pin. If it is found possible to do this it should be incorporated on the 10,000 miles car; as an alternative there is a scheme in which the pin is screwed at its lower end and held in position by a nut; this can be used if the spinning method is found to be impracticable. With regard to the bush, we should like to try 'Tufnol' (manufactured by Ellison Insulations Ld. Perry Bar, Birmingham). This material is, we think, superior to the present linen base bush. The clearance between the pin and bush should be the same as recently adopted on the standard contact breaker arms. E/Lid.{A. J. Lidsey} | ||