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).
Confirming the production of four more composite brake drums after a successful test of the first one.
| Identifier | ExFiles\Box 143\1\ scan0437 | |
| Date | 21th April 1941 | |
| Mr. Bradbury, from Rm{William Robotham - Chief Engineer}/MHR.{M. H. Rigby} Copy to Mr. Wheeler Mr. Roberts. 120g Rm{William Robotham - Chief Engineer}/MHR.{M. H. Rigby}6/LT.21.4.41. COMPOSITE BRAKE DRUMS. So far we have completed one drum of this type, which has been tested and is considered satisfactory. The only serious trouble has been the locating of the liner while casting. This is to confirm that you will make four more drums, using the modified core box whereby the cast iron liner is dropped in the box and the sand rammed inside it. The liners to be zinc plated, as before. We should like to have the specification of the alloy we are using. Rm{William Robotham - Chief Engineer}/MHR.{M. H. Rigby} | ||