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).
Suggestions for improving the lifespan of battery ignition contact points for Phantom, 20HP, and Silver Ghost models.
| Identifier | WestWitteringFiles\Q\January1927-March1927\ 49 | |
| Date | 25th January 1927 | |
| TO EFC. HS.{Lord Ernest Hives - Chair}) FROM R.{Sir Henry Royce} (At Le CanadelHenry Royce's French residence. R2/M22.1.27. 3 DESPATCHED FROM WW. 25.1.27. Copy to ESJ. WGR. BATTERY IGNITION - PHANTOM, 20HP. & SILVER GHOST. X.4652 X 2894 X4041 I feel that with the above it is a very urgent matter to get a definite improvement in the life of the contact points. Many of the following suggestions we between us have made before - (1) Tungsten instead of platinum if nearly as good, because spare new ones are less expensive, and can be fitted instead of doubtful dressing of platinum by novice - i.e. plenty of new spares can be kept by owner. (2) Current should be kept as low as possible by resistance of primary, self induction, or ballast resistance, so as to avoid breaking a large current at slow speeds. (3) The rate of break might be quicker, and the make slower; possibly off-set may do this the easiest and most consistent way. Sharper break must mean less heat, and slower make less bouncing. (4) Rigid and non-bouncing contacts. (5) Condenser of greatest capacity, greater than necessary for maximum spark, but not so large as to materially increase the current. (6) More turns of primary winding but not so many as to require more than 10 V.{VIENNA} for maximum engine revs. of 3,000. Probably there are more that I cannot remember at the moment. All should be an advantage together making enormous difference. How many have we standardised? Are we not getting a bad name that will be difficult to live down? What organisation or scheme of improvement to back work at depots, which should go back to early Silver Ghosts, and even to the 1905. 4 cyl. TT. - (i.e. instruction to depot managers re. battery ignition?) How is it that Lucas can claim for their magneto contact points a life equal to that of the car? See other memo. E.{Mr Elliott - Chief Engineer} will supply a design for "off-set" contact lever. EFC. should write a bulletin of the situation that we can publish to CY., to Repair Dept., and to owners generally, not crying stinking fish, but telling them what spares are recommended and available for different types, and the price of such spares, which should be as low as possible so as to get the parts on a good and lasting basis. I thank E.{Mr Elliott - Chief Engineer} for his memo. of the 17th. In the design for offset rocker stiffen to avoid bouncing. Perhaps some slight damping friction, and perhaps an over-lift damping spring, as on Watford magnetos. (1) | ||