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 testing of a special Watford EW6 Magneto, No.106012, and its performance issues.
| Identifier | WestWitteringFiles\S\March1928-May1928\ Scan021 | |
| Date | 8th March 1928 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} Ry. c. Wor.{Arthur Wormald - General Works Manager} EFCB/T8.3.28. WATFORD EW6 MAGNETOS. The position in regard to these magnetos generally has not progressed so very much further than that indicated in our EFCB/T11.2.28. We have, however, in the meanwhile received from Mr. North a special magneto of this type . No.106012, which has the following differences from the previous EW6 magnetos :- (1) Continuous cam ring. (2) In regard to the advance and retard bearing this is now steel (the continuous cam ring itself) on a brass surface, in place of brass to brass as previously. It will be remembered that all these EW6 magnetos differ (amongst other things) from the EO6 which have a bakelite pinion and aluminium gear wheel, in having both pinion and wheel of bakelite. This machine No.106012 having been passed by us on production test, which includes all the usual items which we expect to be right on a magneto, was handed to the Test Dept. Having been run by them on three different chassis for approximately 150 miles, it was pronounced satisfactory both for electrical performance and noise, but on continuing to run the magneto further it developed a bad knock, i.e. after running a further 95 miles, making 245 miles in all. The machine was then returned to us. In order to find out whether the knock was anything to do with the contact breaker we arranged to put this on an experimental car with a spark gap in such a manner that the magneto would be normally functioning as regards | ||