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).
The grinding and sizing issues of two Bentley cylinder blocks.
| Identifier | ExFiles\Box 103\2\ scan0131 | |
| Date | 30th November 1936 | |
| GWH{George W. Hancock - Head Chateauroux} RHC.{R. H. Coverley - Production Engineer} from Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} KINGSBURY. 30.11.36 BENTLEY CYLINDER BLOCKS. The two cylinder blocks, diamond bored, leaving approximately .002" for grinding, arrived here. We have sent them to be ground standard size, but I was informed that it was not possible to do this as three cylinders were already size in the centre of the bore. I was asked to go and see them measured up before they would start grinding; I did so. The first three bores (front end of the block) were, as sketch shows, over size. This applied to both cylinders. I do not know why this should be the case, but thought you would be interested. To true up the bores, it has been necessary to grind them .010" over-size. They did true up with .005" over-size, but there are no pistons made for this size. We are fitting one of the blocks to a customer's car next week. Would you care to see the other block for finish, size, etc? Rm{William Robotham - Chief Engineer}/G.W. Hancock. | ||