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 cost implications of a design change to the Wraith cylinder head to overcome cracking.
| Identifier | ExFiles\Box 148\2\ scan0016 | |
| Date | 21th October 1938 | |
| To. HY{Tom Haldenby - Plant Engineer} & Rm.{William Robotham - Chief Engineer}....From RHC.{R. H. Coverley - Production Engineer} c.c. Sg{Arthur F. Sidgreaves - MD} & HS.{Lord Ernest Hives - Chair} 1260 RHC.{R. H. Coverley - Production Engineer}1/MC.21.10.38. SWDL{Len H. Swindell} Sales WRAITH CYLINDER HEAD The change of cylinder head design introduced to overcome cracking of valve seat encountered with existing type heads has resulted in a considerable amount of material being rendered scrap. Taking into account all chassis from the commencement of "A" series, there will be a total of 202 cylinder heads to be replaced, details being as follows :- 63 Cylinder Heads finish machined £875. 0. 0d. 83 Cylinder Heads part machined £700. 0. 0d. 56 Cylinder Heads unmachined castings £425. 0. 0d. --- 202 £2000. 0. 0d. --- In addition there will be much expense incurred in other directions such as for replacement valves, guides and other incidental details, also additional charges which cannot be assessed for handling, and general dislocation of production. It is not yet possible to estimate the cost of retrospective action, since chassis are at present tested with existing heads which will be changed at a later date when the new heads are available, and the total quantity of chassis requiring changeovers cannot be, at present, determined. RHC{R. H. Coverley - Production Engineer} [Signature] | ||