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).
Letter from Robinhood Engineering Works concerning modifications to sparking plugs to prevent sparking down the external mica sleeve.
| Identifier | ExFiles\Box 58\3\ Scan073 | |
| Date | 27th March 1924 | |
| COPY OF LETTER FROM:- THE ROBINHOOD ENGINEERING WORKS, LIMITED. PUTNEY VALE, LONDON. S.W.15. K.L.G./ESW. 27th March. 1924. Messrs. Rolls Royce Limited., Nightingale Road, DERBY. Gentlemen, We would again refer to our correspondence on the subject of a modification in the sparking plugs which we supply to your orders, to prevent sparking down the external mica sleeve inside the mica washers. We have been into this matter very closely and find that a very great improvement is obtained by increasing the diameter of this sleeve without increasing its length, which has the advantage of enabling us to make the modification in our standard production without difficulty. We are, therefore, sending to you to-day two dozen plugs modified in this way, marked "K.1.R." and if you approve we shall be pleased to replace all your stock and at the same time we will make this modification standard in the K.1 plug. We have satisfied ourselves as a result of tests at these Works and at Faraday House that this electrical discharge is a result of a condenser effect in the plug itself, and that the actual quantity of current shunted to earth in this way is very small. We should be very much obliged if you could allow us to retain the Coil which you kindly lent to us, for a few days longer. CONTD. | ||