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).
Hardness testing results of a Wraith steering roller.
| Identifier | ExFiles\Box 9\7\ 07-page161 | |
| Date | 31th March 1938 | |
| 650 Mr.Hardy......from RHC{R. H. Coverley - Production Engineer}/EG. c. to RHC{R. H. Coverley - Production Engineer}/Cy. RHC{R. H. Coverley - Production Engineer}/EG.8/DB.{Donald Bastow - Suspensions} 31.3.38. Wraith Steering. Messrs. Hoffmann. R.H. The roller handed to me by RHC{R. H. Coverley - Production Engineer}/Cy., has been sectioned and carefully checked on Rockwell and Vickers machines, and the results obtained by Messrs.Hoffmann are confirmed within very close limits with loads of 10 x 30kgs. on the Vickers machine, our figures being 752 and 763 respectively. The surface is rather soft, probably due to grinding softening, and gives a figure of 713 with a 5 kg. load, although the actual surface hardness would hardly be so high as this, but unfortunately I have no means at my disposal, to give actual surface hardness figures. Goodall RHC{R. H. Coverley - Production Engineer}/EG. | ||