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 design, materials, and manufacturing costs for an armrest on an ED type naval gun.
| Identifier | ExFiles\Box 175\3\ img152 | |
| Date | 13th September 1940 | |
| 3 To Rm.{William Robotham - Chief Engineer} from Ev.{Ivan Evernden - coachwork} c. to Vc. c. to Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} c. to Rm{William Robotham - Chief Engineer}/OTS. c. to Rm{William Robotham - Chief Engineer}/HH.\n̶c̶.̶ ̶t̶o̶ ̶H̶P̶S̶/̶B̶u̶t̶l̶e̶r̶.̶ Ev.{Ivan Evernden - coachwork}7/JH.13.9.40. re Armrest type ED.{J. L. Edwards} Naval Gun. We record in brief the general points which arose during a visit paid to us by a representative of the Rubber Co. in company with HPS{Horace Percy Smith - Experimental Factory Mgr}/Butler. (1) The armrest can not be covered with sorbo rubber with an outer layer of ordinary rubber with any satisfaction. (2) The armrest can be covered with soft rubber to the thickness shown and durometer 30 - 35. The cost of a mould will be approximately £80, if spread over 500 guns 3/2½d.{John DeLooze - Company Secretary} per gun. The rubber weighs 2½ ozs. and will cost from 5/- to 7/6d. per gun. Since only a moderate job could be made of the rubber covering without a mould and because the labour charge would exceed the tool charge, it was agreed that a mould should be made. A drawing of the mould will be supplied to HPS{Horace Percy Smith - Experimental Factory Mgr}/Butler, who will have a casting produced in cast iron. The first 2 armrests for the service trials gun will be made by hand and one will be available by Saturday September 14th, the second will follow as soon as possible. A mould has already been made for the rubber end plugs. Having produced a mould it will be possible for us, should we so desire, to experiment with moulded sorbo covered with rubber. for the armrest. Ev.{Ivan Evernden - coachwork} | ||