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 to Ferodo Ltd. regarding the manufacture of VG.100 friction discs and difficulties with spark recording methods.
| Identifier | ExFiles\Box 141\2\ scan0305 | |
| Date | 6th July 1939 | |
| 1180 EXPERIMENTAL DEPARTMENT. Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}1/JH. 6th. July, 1939. Ferodo' Ltd., Chapel-en-le-Frith. For the attention of Mr. Shilton. Dear Sirs, In confirmation of our telephone conversation of yesterday we agree to the method of manufacturing the VG.100 friction discs, that is by bonding the VG.100 on to a Ferobestos disc. I have asked Mr. Martindale what his experience of using sparks for Timing or Recording had been. He states that with the ordinary R.R. coil the marks are difficult to read and vary with the type of paper used. Pole finding paper did not give much improvement though no doubt there are some compounds which might help in this matter. The other difficulty was the fact that the spark does not alway travel in a straight line and unless the two electrodes are very close to the paper (almost in contact) quite large variations are noticeable. The type of paper might have a bearing on this trouble. We trust you will soon have the test rig in operation and would be glad if you would let us know when it is complete. Yours faithfully, FOR ROLLS-ROYCE LTD. | ||