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).
Complaint about the eccentricity of Bentley rear brake drums and establishing manufacturing tolerances.
| Identifier | ExFiles\Box 120\1\ scan0205 | |
| Date | 19th August 1937 | |
| Mr/AFM.{Anthony F. Martindale} from RHC{R. H. Coverley - Production Engineer}/Cy. c.c. to RHC.{R. H. Coverley - Production Engineer} 1028 RHC{R. H. Coverley - Production Engineer}/Cy.3/LS.19.8.37. File BENTLEY - REAR BRAKE DRUMS. G.100981. Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale}3/AP. 29.6.37. ? We have investigated the complaint of eccentricity of brake drums and agree that the grinding fixture is out of condition. The necessary action has been taken to provide the correct equipment, and this is now in hand in the Tool Room. It must be appreciated that a slight manufacturing error of eccentricity must be allowed. The ball race bores in the hubs (made by Messrs Dunlops) are not dead true with each other, as they cannot be produced without some limit of error. Working clearances are required on the fixture to allow for limits on sizes of ball race bores, and whilst every effort is being made to make a very accurate job, we cannot guarantee to produce all pieces without error, and have therefore fixed the limit of .002 indicator reading for eccentricity. RHC{R. H. Coverley - Production Engineer}/Cy. Cy | ||