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 on a steering column ignition switch fitted with a Mouldensite insulated drum.
| Identifier | ExFiles\Box 53\3\ Scan142 | |
| Date | 11th May 1923 | |
| EFC. 11.5.23. STEERING COLUMN IGNITION SWITCH FITTED WITH MOULDENSITE INSULATED DRUM IN PLACE OF STANDARD STABALITE INSULATED DRUM. This switch was fitted up with a belt pulley and driven at 40 r.p.m., connected up in the usual way to battery and magneto ignition systems running on the bench. It was run in all for a period of 25 hours, totalling 60,000 revs, corresponding to a 10,000 mile test with six switching-rounds per mile. The battery ignition was switched on for 23 hours of this, corresponding to 55,000 revs. It was noticed that after running 7.5 hours, equal to 18,000 revs. the switch started to squeak, which continued to the end of the test. INSPECTION. After running, the switch was dismantled for examination. When the drum was withdrawn from its case a fair amount of dust came out of it, composed of brass and mouldensite, the brass coming from the small bearing bush which was found to be considerably worn. (N.B. The switch was purposely not oiled during the test to prevent oil getting on the contacts. The wear would be due to the side pull of the driving belt, and would not occur in use on the car). It was also noticed that the insulation was only slightly burnt at the running and trailing edges of the segments, due to sparking, this being worse in the case of the magneto segment. C.A.P. | ||