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 Thos. Firth & John Brown Ltd. discussing methods for preventing corrosion on road springs.
| Identifier | ExFiles\Box 154\2\ scan0119 | |
| Date | 15th July 1938 | |
| c. Hs.{Lord Ernest Hives - Chair} c. Rm.{William Robotham - Chief Engineer} c. ROY{Sir Henry Royce}/Les xx 2424. BY.5/C. -------- Messrs. Thos. Firth & John Brown Ltd., Atlas and Norfolk Works, Sheffield.1. Dear Sirs, ROAD SPRINGS. 15th. July 1938. With reference to my letter of yesterday's date (ref. BY.7/G.{Mr Griffiths - Chief Accountant / Mr Gnapp}) in connection with a possible future method of the production of springs, in the interests of economy I would like to point out that whilst the proposal for treating a spring in a cyanide bath is beyond question an advantage if worked under controlled conditions, the further suggestion in regard to the possibility of preventing corrosion by the production of a magnetic oxide skin is not in this position, and I wish to make it plain that I appreciate that there may be difficulties in arriving at the end proposed. The point I have in mind is, of course, that having treated the spring with cyanide, it will have been necessary to have same descaled, and the production of a further oxide coat may result in the reproduction of a slight decarburisation, but the matter should be decided by experiments and not looked upon as a matter for discussion. If the production of a skin of magnetic oxide ultimately proves not to be practicable, then some other method of protecting the spring must be provided. In producing a coat of cadmium it is most important that the spring should not be etched either chemically or electrolytically, as this will undoubtedly in certain cases result in intercrystalline penetration, which spells rapid failure. Cleaning the spring would have to be done mechanically if one is forced to use plating as a protection, | ||