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 inspection of magnetos, discussing faults, the use of magnesium alloy, and performance after a race.
| Identifier | ExFiles\Box 43\4\ Scan182 | |
| Date | 20th September 1929 guessed | |
| -3- Assisted by one or two visits from B.T.H. representatives, steps were taken to make critical examinations of all the magnetos in question for similar faults, and in one or two other cases similar faults were apparent, some of these were corrected by the B.T.H. Co. as occasion arose, but we still have four magnetos opened up for inspection after the return of the engines, three of which exhibit looseness of the laminated flux carrying limbs, and all of which exhibit some wear on the advance and retard bearing surfaces. It will be seen therefore, that though we did not have any actual failure, there appeared at the time a certain amount of risk of possible trouble with these B.T.H. magnetos, which fortunately did not interfere with the winning of the Race. It would appear from the above that the use of magnesium alloy is a hazard we should not again take in similar circumstances. Apparently Messrs.North appreciated this hazard in definitely refusing to incorporate the use of this alloy in their SP.{Mr Spinney}12/5 magnetos supplied for a similar purpose. As already referred to, only one pair of these magnetos has been run on an "R" engine. This gave little trouble apart from the fact that certain screws worked loose. The details of running and inspection of these magnetos have been made the subject of a separate report. EFC. | ||