Letter to Joseph Lucas Research Laboratories detailing test results and criticisms of a Lucas battery ignition system.
| Identifier | ExFiles\Box 164\5\ img097 | |
| Date | 20th November 1931 | |
| X6018 c. EV. {Ivan Evernden - coachwork} Hs {Lord Ernest Hives - Chair} /Wst.5/AD. November 20th, 1931. Dr. E.O. Turner, The Joseph Lucas Research Laboratories, Well St. {Capt. P. R. Strong} Birmingham. Dear Dr. Turner, Lucas Battery Ignition. We have now completed tests on the Lucas ignition distributor and ignition coil which you so kindly loaned to us for examination. Dealing with the distributor first, we certainly think this is a satisfactory design and our only criticisms of it are as follows :- (a) The contact point surface condition is poor after an equivalent of 10,000 miles running and caused bad misfiring at low speeds. We attribute this to the rigidity of the contact screw support, as we have found from experience that very slight flexibility at this point certainly improves the condition of the contact surfaces in that it allows the contact bedding to spread all over the surface evenly and so prevent undue local heating which produces the pitting. (b) The plating on the lever is too thin and is easily dissolved by the nitrous oxides present in the distributor head. On the lever we tested, the whole of the plating was dissolved leaving the copper finish. We find that the wear on the brass sparking segments in the distributor was very small and we should like to know if this is due to the particular combination of metals used i.e. brass and nickel. The condenser capacity appears to us to be rather low. We should be interested to know what factor in your opinion governs the size of the condenser, personally we find it to be contact life. We are pleased to see that you have allowed a generous leakage distance in the distributor head, we think this is an important point. | ||
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).