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).
Instructions regarding the properties and performance of tungsten contact points.
| Identifier | ExFiles\Box 35\6\ scan 136 | |
| Date | 7th May 1925 | |
| RR 238 (150 BKS.) (SH57. 29-6-20.) MP 224355 X. 2894 ROLLS-ROYCE LTD. INSTRUCTIONS. To: E.H.B. Order No. WB{Mr Brazier/Mr Bell} 29 Customer's No. X 2894 Date: 7-5-'25 Tungsten contact points The following tabulated items relating to Tungsten points are gleaned from the file (X2894) and show the principal points of interest regarding these points. a) Points must be made of pure tungsten for reliability. b) The performance of tungsten points improves, with the increase of the size of the point, and area of contact. c) Tungsten points run better with reduced current 1 amp or less. d) Oxidation occurs rather rapidly with tungsten, causing a resistance on contact. This oxidation is Signed: Contd This Sheet must be filed on completion of the work. | ||