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).
Offering criticisms on the simplified Wraith III main switch to make it more economical to assemble.
| Identifier | ExFiles\Box 168a\2\ img317 | |
| Date | 8th May 1937 | |
| To E.{Mr Elliott - Chief Engineer} From RHG/J.{Mr Johnson W.M.} Smedley. c. to Ey. c. to HPS.{Horace Percy Smith - Experimental Factory Mgr} 6139 RHC{R. H. Coverley - Production Engineer}/JS.{Mr Johnson's Secretary}6/WJ.8.5.37. WRAITH 111 MAIN SWITCH (BY/BS.{A J. Barnes - Assistant Manager}2/W.26.4.37). With reference to the Wraith 111 simplified main switch we have studied this very carefully from a Production point of view and we notice that generally speaking the economies have been effected to the pressings and machining etc., but we do feel it would also be an advantage if it could be made more economical to assemble. To illustrate our meaning we offer the following criticisms - (1) The hinge remains unaltered - this is a skilled Fitter's Job which necessitated filing and adjusting to obtain a .004" air gap. We should be pleased if this could be simplified. (2) The laminated contacts remain unaltered from an assembly point of view, and these also require bedding by a very skilled operator and also take a long time. (3) The carbon contacts remain unaltered - these also require bedding. We would suggest some tests be carried out with a view to deleting these altogether. (Bosch Co., Messrs. Lucas & Messrs. Delco Remy switches work quite satisfactorily without these.) (4) We would prefer the non-inductive resistance to be wound on the core of the main coil as this would be easier to wind and more economical. (The S.U. Co's. Electric Petrol Pumps are wound like this.) (5) Copper would be an improvement in place of brass for the main contact although this is a technical point. RHG/J.{Mr Johnson W.M.} Smedley. | ||