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 for Ferflex Braided, single-core electric cable.
| Identifier | ExFiles\Box 168b\2\ img088 | |
| Date | 30th November 1922 | |
| ROLLS ROYCE LIMITED SPECIFICATION NUMBER: 250. Ferflex Braided. MATERIAL: Electric Cable. 600 Megohm Grade. TYPE OF CORE: Single. CORE SIZE: 40/36 OUTSIDE DIAMETER: .200" Maximum. CONDUCTOR: High Conductivity Tinned Copper Wire DIELECTRIC: One layer pure rubber and two layers Vulcanizing Rubber. The rubber in each case shall be equal in quality to first grade Plantation Rubber. The Vulcanizing Rubber shall contain at least 40% Pure Rubber. Mineral Fillers only to be used. Proportion by weight of Sulphur shall not exceed 2.5%. The radial thickness of the pure rubber must be at least .006. Total radial thickness of dielectric must be at least .035. PROTECTIVE COVERING: Oil Resisting Varnished Cambric Tape applied spirally. Protected overall with a Ferflex Braid of 36 SWG. Tinned Copper Wire. | ||