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).
Cost analysis for inlet valves with figures from Morris Motors, including material specifications and a comparative note on gearbox grinding costs.
| Identifier | ExFiles\Box 148\5\ scan0319 | |
| Date | 28th April 1938 | |
| 1260 RHC.{R. H. Coverley - Production Engineer} from Rm.{William Robotham - Chief Engineer} c. Hs.{Lord Ernest Hives - Chair} Rm{William Robotham - Chief Engineer}3/R.28.4.38. COST OF VALVES. Herewith particulars from Morris Motors of the estimated cost of an inlet valve made to our drawing which we sent them. We have added 250% to the labour cost with a view to getting a total cost figure:- Cost of material ........ 3.1d. Cost of all operations to produce forging, including cutting off, rough grinding, forging and inspection .... .638d. Total: 3.738d. (With 250% overheads 5.3d) Morris state this figure is for bare labour and material charges, and includes no overheads. Material Specification. Carbon .6 Silicon 1.5 Manganese .5 Chromium 6.5 (quotations we have had from outside are 10d each for lots of 5,000). ---------------- Incidentally, you will remember we asked Boyle about the cost of grinding compared with the cost of shaving. I have now received a reply which is as follows:- "With regard to the gearbox business, I have discussed the question of the cost of gear grinding with Mr. Harriman at some length. We can get gears ground for, approximately, 3/- per pair. This, vastly more expensive | ||