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 coil winding, including primary and secondary layers and insulation.
| Identifier | ExFiles\Box 69\1\ scan0291 | |
| Date | 3rd January 1930 | |
| EFC5/AD3.1.30 contd. -2- Primary winding as on D.72428. 2 turns of .010 empire cloth over primary winding as base for secondary 2.850 wide. Joint of secondary winding to primary. start off with secondary winding as described on D.72428 but flexible started off at secondary end to overlap secondary layers. Secondary winding 18,000 turns of 42 SWG. (.004) enamelled wire (.00475" overall dia.) First 6 layers of secondary inter layer insulation 4 turns of .00075 oil or waxed paper followed by 3 turns per layer of similar paper for remaining layers 2.850 wide. Coil finished off as described in D.72428. EFC. | ||