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).
Comparison of scleroscope hardness tests on experimental and standard grey fibre samples.
| Identifier | ExFiles\Box 69\1\ scan0413 | |
| Date | 4th January 1927 | |
| X4646 To EFC. FROM RHC.{R. H. Coverley - Production Engineer} RHC{R. H. Coverley - Production Engineer}1/BE.4.1.27. RE BONE GREY FIBRE -X.4646 With reference to EFC4/T.21.12.26. and samples of grey fibre attached. We cannot measure the brinell hardness test but have taken a scleroscope test of this material. Experimental piece supplied - 58-60. Standard Piece " - 62-64. It will be seen by the figures that the standard piece shows to be slightly the better - it does not follow of course, that the wearing qualities will be as good as the Experimental sample submitted, which is proved by your tests. RHC.{R. H. Coverley - Production Engineer} | ||