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).
Visit to Ferodo's to discuss the properties and testing of various interleaving materials.
| Identifier | ExFiles\Box 154a\2\ scan0260 | |
| Date | 11th March 1940 | |
| REPORT OF VISIT TO FERODO'S. 11.3.40. Subject : INTERLEAVING. The reason for the visit was to discuss a new type of interleaving they are making for us, and to get their opinion on the coefficient of friction of the various materials we have tried, and are proposing to try. The life of a piece of interleaving depends upon three factors: thickness, coefficient of friction, and toughness. Toughness is a somewhat indefinable factor but is bound up with the hardness of the material. The coefficient of friction does not depend on the hardness but on the material and it's treatment. Thus, the waxed cardboard materials like the original American stuff and the Ferodo Jackson board, have a very low coefficient of friction. Next, is Spauldite, the resin treated cardboard; then their new stuff V.G.91 and the materials with the highest coefficient are the resin treated cotton base materials like Tufnol. This was the opinion expressed by Mr. Langley, and he proposed to substantiate it by carrying out tests on suitable samples of five different materials. V.G.91; Spauldite; American and Jackson board both plain and bakelised. In addition to measuring the coefficient of friction they are also going to measure the rate of wear of the various materials. It was decided to base the measurements upon a load of 1,000 lbs. per spring spread over an area of 2 sq." at either end of the spring, giving a pressure of 250 lbs. sq. in. - Continued - | ||