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).
Issues with ignition coil insulation, materials, and standardisation.
| Identifier | ExFiles\Box 45\4\ Scan185 | |
| Date | 26th July 1923 | |
| X4079 To EY. from EFC. c. By/DS. c. EP{G. Eric Platford - Chief Quality Engineer} c. Sft.{Mr Swift} for Mr. Brock. EFC1/T26.7.23. X.4079 - RE IGNITION COIL. X3445 Answering your Ey5/P25.7.23, I am certainly in agreement with producing an insulation between the primary layers. As you know, I have always made a point of good primary insulation, and as regards the present coil had always been assured that the introduction would result in an amount of reduction of the secondary winding which I hade decided was unwarranted. Therefore, it had appeared to me that the only way out of the difficulty was to go to the longer coil in which direction we have recently been working. I am also in agreement with you that the extra original insulation should also be introduced on the new coil, though on the half dozen or so coils we have run on chassis, we have had no suggestion of a failure on this score. Admittedly the mistake in the whole matter with these ignition coils has consisted in not standardising the longer coil in stabalite case at the time of our report EFC2/T29.1.23 and R's memos R6/M29.1.23 and R5/M31.1.23. The reason for the mistake is clearly that we felt we were so near to the final solution of the difficulty in using mouldensite cases. It now appears that we are not safe with encasing any kind of coil in any form of bakelite moulding material whatever. This, however, we have only been able finally to decide within the last few days owing to failure on test of a coil in a Redmanol case. EFC. | ||