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).
Test report detailing the results of speed and temperature tests on Bakelite and Mouldensite moulding materials.
| Identifier | ExFiles\Box 50\5\ Scan094 | |
| Date | 13th July 1922 | |
| EFC {E. Fowler Clarke - Electrical Engineer} 1/T13.7.22. -2- Contd. | Date of test. | Moulding material. | Ref. Lcttr. | Carcase temp. reached previous to speed burst. | Test speed. | Duration of speed test (min) | Result. | Further remarks | |---|---|---|---|---|---|---|---| | 7.7.22. | 1. Bakelite. | k | 130° | 6000-6400 | 6 segments flew out. | 6 segments flew out. | Solder unaffected. | | | 2. Mouldensite | i | 130° | 6000-6400 | 18 | Segments O.K. but comm. had loosened & moved on ferrule. | Solder melted. | N.B. Owing to the arrangement of the heater the two commutators on test together would not be precisely at the same temperature and in cases where the solder melted it is invariably on the comm. which would be at the higher temperature. | 12.7.22. | 1. Mouldensite. | i | 135° | 6000-6450 | 4 | O.K. | Solder unaffected. | | | 2. " | l | 135° | 6000-6450 | 4 | O.K. | Solder melted. | | 12.7.22. | 1. " | i | 135° | 6000-6500 | 10 | O.K. Solder unaffected. | 4 minutes at 6000 and 6 mins. at 6500. | | | 2. " | l | 135° | 6000-6500 | 10 | O.K. | | N.B. Mouldensite commutator (ref. l) had 6 1/8" radial holes drilled in the ferrule so that the moulding material could run into these holes, the idea being to prevent the commutator coming loose on the ferrule, as happened in two previous cases on test. EFC. {E. Fowler Clarke - Electrical Engineer} | ||