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).
Specification and test report for an ignition coil component, including a dimensional drawing and performance data.
| Identifier | ExFiles\Box 52\3\ Scan256 | |
| Date | 25th April 1917 | |
| Contd. -2- [Drawing of a component with dimensions 1 1/16", 9/16", 1/4", 2 1/4", 2 3/8"] 2 End caps of Stabeloid moulding. Mica tube .015" thickness between the primary and secondary and three layers of Empire Cloth of .010" thickness. The core was insulated by two layers of vanilla paper .0075" thick and 1 layer of .010" Empire Cloth The core consists of 232 pieces of .036" Iron 5¼" long. Table of speeds and consumption using 12 gaps (spark) 5mm. wide plat:points contact breaker set .025". Speed. Consumption. (amps) 1500 1.05 starts to miss. 1000 1.55 700 1.9 300 2.35 150 2.55 Sparking at plat:points nearly nil . The current density of the spark is very poor and seems to me of poor igniting quality. When used as a 6 cylinder coil (1 break) the speed goes up to 1900 revs. R.R. 235A (500 T) (S.D. 408. 25-4-17) Bm. 2/156/13. | ||