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).
Experimental bench test schedule detailing the design and performance of a Watford (aero) magneto.
| Identifier | ExFiles\Box 43\4\ Scan242 | |
| Date | 18th February 1930 | |
| X4021. MAGNETO TESTS TO EXPERIMENTAL BENCH TEST SCHEDULE DETAILS OF MAGNETO DESIGN AND PERFORMANCE. Date :- 18-2-30 Magneto on test :- Watford (aero) Maker :- Messrs North and Sons Ltd. X. No. :- 4021 Type :- IS12. or SP{Mr Spinney}12-2. No :- 83132. (1) Weight in pounds :- 16.875 (2) Remarks re mechanical and electrical design :- Pure inductor type of magneto with rotating laminated inductor rotor in association with four short Cobalt steel bar magnets. Fully screened for radio having cast aluminium distributor shield with distributor permanently fastened to it as one unit. Bakelite distributor gear wheel, steel pinion. Oilway to each bearing. Small light construction contact breaker with Duralumin lever. Spigot mounted with gland in each rotor bearing to prevent ingress of hot engine oil vapour to contact breaker. (3) Length of H.T. safety gap :- 8.6 mm (altered from 7.7 mm by ourselves) 5 | ||