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).
Failure of commutators on R.60 and R.80 Dynamos due to being built with miconite instead of pure mica, and proposing their replacement.
| Identifier | ExFiles\Box 168a\3\ img021 | |
| Date | 30th March 1940 | |
| 6142 To HPS{Horace Percy Smith - Experimental Factory Mgr}/HL. cc to Rm{William Robotham - Chief Engineer}/RC{R. Childs}/GAR. Rm{William Robotham - Chief Engineer}/RC.{R. Childs}5/JH.30.3.40. Faulty Commutators on R.60 and R.80 Dynamos. We have had a number of failures of the latest fully-driven dynamos which can only be due to the fact that the commutators of the machines are wrongly built up with miconite instead of pure mica. To avoid future trouble it is proposed to build a number of 72 - segment commutators with the correct material (pure mica) supplies of which are at present at Sleek Lane. The faulty commutators will then be drawn off the machines and the new ones fitted. In all, there are six machines to be corrected, but two should be completed to commence with. Will you please make the necessary arrangements for this work to be carried out. Rm{William Robotham - Chief Engineer}/RC.{R. Childs} | ||