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 comparing the performance of different moulding materials under speed and temperature stress.
| Identifier | ExFiles\Box 50\5\ Scan093 | |
| Date | 13th July 1922 | |
| EFC {E. Fowler Clarke - Electrical Engineer} 1/T13.7.22. Date of test. | Moulding material. | Ref. lettr. | Carcase temp. reached previous to speed burst. | Test speed. | Duration of speed test (Mins) | Result. | Further remarks. 1.7.22. 1. Plain Elo. | h | 108º | 6400 | 3 | O.K. | This comm. had previously undergone 3 high temp. speed tests as rept for 29.6.22. on previous table. 2. Mouldensite. | i | 108º | 6400 | 3 | O.K. | The segments used in the building up of this comm. differ from those in the previous mouldensite comm. (ref.g) in a manner indicated by further sample now sent labelled 4. 3.7.22. 1. Plain Elo. | h | 120º | 6250 | 1 | Burst. 2. Mouldensite. | i | 120º | 6250 | 3 | O.K. N.B. It being understood that the figures given for the comm. which remained O.K. refer to a continuation of the test, after the first comm. had burst, so that really the second comm. was subjected to both these tests. 4.7.22. 1. Mouldensite | i | 102º | 6400 | 3 | O.K. 2. " | j | 102º | 6400 | 3 | O.K. Solder unaffected | This comm. was the second one similar to i. Lumps of solder were put on the radial faces of this and subsequent comm. segments to give an indication if the actual comm. segment temperature should exceed the melting point of the solder, believed to be about 180º. 4.7.22. 1. Mouldensite | i | 120º | 6500 | 3 | O.K. 2. " | j | 120º | 6500 | 3 | 5 segments flew out. | Solder unaffected. Contd. | ||