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).
Investigation into die castings and less costly alloys for manufacturing components.
| Identifier | ExFiles\Box 142\4\ scan0038 | |
| Date | 23th November 1936 | |
| Our copies - please return. x1702 Thanks - Hs.{Lord Ernest Hives - Chair} from Rm.{William Robotham - Chief Engineer} Sg.{Arthur F. Sidgreaves - MD} E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer} SRt. RHC.{R. H. Coverley - Production Engineer} Hl. Rm{William Robotham - Chief Engineer}3/R.23.11.36. DIE CASTINGS & LESS COSTLY ALLOYS. Further to Rm{William Robotham - Chief Engineer}21/MJ.2.11.36., we have now had a further letter from Leylands and visited the Birmingham Aluminium Co. We attach Leyland's letter. They ask us to treat the information as strictly confidential. The attached report Rm{William Robotham - Chief Engineer}/Smth4/R.23.11.36. covers the information so far obtained. The conclusions are probably optimistic. The investigation revealed one or two surprising facts which are as follows:- (a) If we assume that we have under-estimated our tool costs by 100% (they are an approximation on pieces we saw at Birmals), it should still pay us to use dies provided the design remains unchanged for 6 months' output of existing numbers. (b) The Austin crankcase indicates that die casting limitations on design are not nearly so great as we previously thought. (c) Reasonably good alloys, which may be permissible on certain parts, are obtainable at prices that are much lower than we had hitherto suspected. For instance, RR.50 £135 per ton, L.5 £89 per ton. (d) Die casting in most cases improves the strength of the alloy very considerably. It certainly gives a finish which we cannot approach with sand castings. It saves weight in any given alloy. Birmals are very willing to co-operate with us, and it is proposed to make a test case of the Wraith crankcase, which is a slightly modified Bentley, and get a detailed figure for tool costs and the resultant saving in the cost of castings. This part can hardly have a life of much less than two years. Rm.{William Robotham - Chief Engineer} | ||