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).
Specifications for Workshop Twin Flex and Ferflex Braided electric cables.
| Identifier | ExFiles\Box 168b\2\ img116 | |
| Date | 14th October 1923 | |
| 14.10.23. SPECIFICATION NUMBER 263. (WORKSHOP TWIN FLEX) MATERIAL. Electric Cable. TYPE OF CORE. Single. CORE SIZE. 22/38. OUTSIDE DIA. .115 maximum each cable. CONDUCTOR. May be either tinned high conductivity copper wire or single cotton covered plain H.C. copper wire. DIELECTRIC. Two layers of pure rubber for each core. Each layer to be at least .005 radial thickness. PROTECTIVE COVERING. Each core should be protected with a single cotton lapping. One core whire and one core red. Cotton braided and compounded black. Workshop finish. The twin cables shall then be twisted together. SPECIFICATION NUMBER 264. (FERFLEX BRAIDED) MATERIAL. Electric cable. TYPE OF CORE. Twin. CORE SIZE. 2-23/36. OUTSIDE DIA. .250 maximum. CONDUCTOR. High conductivity tinned copper wire. DIELECTRIC. One layer of pure rubber and one layer of V.I.R. One core white V.I.R. and the other red V.I.R. Total radial thickness of dielectric .022. PROTECTIVE COVERING. Cores to be twisted together and wormed circular with cotton. Taped and protected overall with a Ferflex braid of 36 S.W.G. tinned copper wire. NOTE. Special for Repair Department use, and should not be used for new production. | ||