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 specifications and requirements for manufacturing aluminium brake drums.
| Identifier | ExFiles\Box 115\1\ scan0305 | |
| Date | 18th March 1937 | |
| To HPS.{Horace Percy Smith - Experimental Factory Mgr} from Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} 1028. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}5/AP.18.3.37. ALUMINIUM BRAKE DRUMS. With reference to our memo Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}19/JH.9.3.37. in which we asked you to make some heavier front aluminium brake drum castings. In consequence of having made the test described in Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}20/JH. 9.3.37., we now know the type of liner fixing we require. The fix-ings are to be of the same general type as used for drum Ex.21590. Four look plates per drum Ex.21593 will be required, and the slots in the liner must suit these. Four reinforcing plates GB.2396 will be required per drum. Instead of the screws Ex.21591, we want 4 screws Rm.{William Robotham - Chief Engineer}340 per drum. The liners are to be nickel plated to a thickness of about .0005 or .001 to prevent rusting. Plating not to polished. We want 2 pairs of drums completing to these details. One pair is to be sent out to Sr. in Paris for his trials car. The inside of the liners should not be finished machined and no hubs are required. The other pair to be fitted to the front of 5.B.1V. using the present hubs. The brakes of 5.B.1V. will need relining all round with Halo III. material to be supplied by Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} A screw driver Rm.{William Robotham - Chief Engineer}341 will be necessary to insert screws Rm.{William Robotham - Chief Engineer}340. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} | ||