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).
Comparing die-casting quotations for an aluminium Bentley crankcase from three different suppliers.
| Identifier | ExFiles\Box 142\4\ scan0078 | |
| Date | 27th January 1937 | |
| Sg.{Arthur F. Sidgreaves - MD} from Rm{William Robotham - Chief Engineer}/Smth. HS.{Lord Ernest Hives - Chair} c. to E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} c. to RHC.{R. H. Coverley - Production Engineer} DIE CASTINGS. We have received a number of quotations from The Birmingham Aluminium Casting Company, for die casting aluminium engine pieces, and in the majority of cases have been disappointed to find that the savings anticipated in Rm{William Robotham - Chief Engineer}/Smth.4/R.23.11.36. have not been realised. When we discussed the question of die casting with The Birmingham Aluminium Casting Company, we had the impression that they were not anxious to do this work for us, since their object was to sell aluminium and not to make dies. We therefore asked Roy.{Sir Henry Royce} to get quotations for the Bentley crankcase lower half from other firms, regarding this piece as a typical one. The following prices were quoted - | Firm. | Tools. | Quantities of 200. | Material. | |---|---|---|---| | The Birmingham Aluminium Casting Co. | £230 | 78/- | RR.50. | | Heritier. | £300 | 75/- | RR.50. | | Mills. | £400 | 47/6 | RR.50. | Slight modifications to design would be needed to make this piece a die casting proposition. The present factory cost for this casting is 70/2., in RR.50. We estimate that 8/- could be saved on surface finishing labour if we adopted die casting, bringing the relative cost of the piece as made now to 78/-. We are now making 27 Bentley and 25/30. chassis a week. At this rate of production the die cost distributed over six months output (700 chassis) would be 11/6. per car. This is with the Mills quotation. The actual cost of the die casting would then be 59/- per piece, giving a saving of about 19/- per car. This is within 1/- of our estimated saving for this piece. continued. | ||