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).
Letter to Messrs. North & Sons, Ltd. regarding the testing and performance of Watford IS.12 magnetos.
| Identifier | ExFiles\Box 43\4\ Scan285 | |
| Date | 17th May 1930 | |
| X4021. EFC3/AD. 17th May, 1930. X4513W. Messrs. North & Sons,Ltd. Whippendell Rd. Watford. Dear Sirs, Watford IS.12. Magneto No.98034 and Watford IS.12 magnetos generally. You will recall that as a result of our report having been sent to you on the condition and results of bench test after type test of magneto No.98034, you expressed a wish that as it was not possible for you to offer any suggestion as to the cause of the imperfect action of this magneto without making a full examination, you would be pleased if we could conveniently send it to you to enable you to examine and report. With this in mind we have obtained the permission of the A.I.D. here again to return to you this machine and have accordingly taken the necessary steps in that direction. The magneto is being despatched to you. The reference of your letter is CHK/VS.{J. Vickers} of April 7th. As explained to your Mr.Allen we have never been completely satisfied on bench test with the performance of this particular machine, which has never been as good as its companion No.98033 even after returning it to you on a previous occasion when we believe you found some error in the armature extensions. In regard to the question of the 8.5 mm. safety gap in place of the 7.7 mm, if we remember rightly you were going to take this matter up with Farnborough pointing out that it is our recommendation, and also that it would bring your safety gaps into line with those of | ||