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).
Experiments with different filler materials for coil cases, including wood, asbestos, and bakelite.
| Identifier | ExFiles\Box 45\4\ Scan071 | |
| Date | 9th November 1922 | |
| Contd. -2- EFC2/T9.11.22. Regarding your suggestion of mahogany or teak wood dust, the makers have previously informed us that only one or two very special kinds of wood can be used as filler. At present wood flour from a particular kind of Norwegian wood is received as such in sacks for the purpose. It would appear as you suggest that the distributor must also be wrong though we do not experience any sign of trouble using a coil in a stabalite case but with a bakelite distributor. With regard to your suggestion re cases being properly cured, we have made the experiment of giving a coil case extra time in the mould for this purpose, but without improvement. You will see from my other report that mouldensite material seems to be better than Elo. We now have nearly ready a coil in a case composed of Elo material but with asbestos filler in place of wood. This does not produce such a nice finished looking case but the result is hoped to be an improvement. Meanwhile an experiment is being conducted with a coil in a bakelite case from the Marmon car. EFC. | ||