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).
The performance of bone grey fibre for battery ignition rubbing blocks, with a sample provided for comparison.
| Identifier | ExFiles\Box 69\1\ scan0410 | |
| Date | 4th December 1926 | |
| X4646 To Wd.{Mr Wood/Mr Whitehead} from EFC. EFC2/T4.12.26. X.4646. BONE GREY FIBRE. X8796 Herewith we hand you a piece of the bone grey fibre from which we have made a number of rubbing blocks for the battery ignition, which blocks have worn particularly well. You will remember it was arranged to let Messrs. Norths have a piece of this to compare on their magnetos with their standard material, as we have found that on a properly ground cam this runs remarkably well without any lubrication. I understand our own cams are finely ground, and lapped for still further improved surface. EFC. Material herewith, | ||