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 best plating methods for cast iron liners intended for aluminium brake drums.
| Identifier | ExFiles\Box 121\1\ scan0408 | |
| Date | 3rd January 1941 | |
| 1029 To Rm.{William Robotham - Chief Engineer} from Rm{William Robotham - Chief Engineer}/GB. Copy to Rm{William Robotham - Chief Engineer}/GB Surely we can control the rate of cooling in the liner in a die-casting Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}/GB.7/ET.3.1.41. Mr. Gresham was asked for advice on the best plating for C.I. liners, which are to be cast in aluminium brake drums. Mr. Gresham's first recommendation was copper since this was readily adsorbed by the aluminium so that a good bond might be expected. As a second line of attack he thought that a touch of nickel on the copper would be well worth trying. Mr. Gresham is arranging with Mr. Wheeler for small samples of iron to be plated as above and cast in aluminium. Mr. Gresham feared that even if a good bond were obtained it might be lost during the cooling due to the very different rates of contraction of iron and aluminium and he suggested the use of austenitic iron for the liner. It was pointed out that this was more expensive and that, in the drum design, the thickness of C.I. had been kept down in order to reduce the stresses in the aluminium. The three machined liners have had the thread turned away except for a distance of ¼" at each end. Two of these are to be copper plated and cast into drums without waiting for Mr. Gresham's tests. Rm{William Robotham - Chief Engineer}/GB. G.B. | ||