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 maintenance and cleaning of battery ignition contact points.
| Identifier | ExFiles\Box 26\2\ Scan268 | |
| Date | 13th September 1926 | |
| To-Hm.{Capt. W. Hallam - Head Repairs} from EFC. By.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair} BP. MX.{John H Maddocks - Chief Proving Officer} Br.{T. E. Bellringer - Repair Manager} Py/NHW. Hm{Capt. W. Hallam - Head Repairs}/NRC.{N. R. Chandler} Demonstration Class. x8782 EFC4/T13.9.26. BATTERY IGNITION CONTACT POINTS. X4652 x8782 Apparently a good deal of platinum is removed from battery ignition contact breaker points unnecessarily, it perhaps being thought that when trimming the points it is necessary to make a clean surface all over before allowing them to continue. Points should not be cleaned up except the merest superficial cleaning off of dirt or oxidation, unless (1) They are bedding incorrectly on a portion of the edge only, in which case bedding should be improved, but not necessarily to the extent of the whole surface. (2) A definite pip has formed on the contact breaker lever point with its corresponding depression on the screw point. If this is allowed to attain too large proportions the tip of the pip may reach the steel base on the point screw and dirt will be produced, with consequent misfires. It is generally advisable partially to remove the pip in order that the actual contact may be transferred to a ring around its base. It certainly does not appear necessary to clean off both pip and hollow as soon as they have formed sufficiently to be noticed. In general we may say that it is not necessary to clean up points completely, but only to re-provide sufficient clean metallic contact area to give the points a fair chance. The whole point is to avoid the unnecessary removal of useful contact point material. Contd. | ||