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).
AC.2 and AC.7 bearings, clarifying required allowances and issues with material growth.
| Identifier | ExFiles\Box 114\3\ scan0030 | |
| Date | 8th December 1938 | |
| To By... from Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux}29/N.8.12.38. Re: AC.2. Bearings. I have received your memo BY.6/G.30.11.38, and have read same with interest. It clears up the position which had been puzzling us . Your explanation is very clear and we now understand why the oil flow had been misleading. The one point now which I would like to again draw your attention to is that the AC.7. bearing material grows more than the experimental allowed for, which we have repeatedly found on new cars. I have reported that the maximum allowance required as instructed to the Works i.e. .00275 and not .00250" which is not sufficient for the connecting rods. I believe the instructions are minimum .00250, maximum .00275" whereas we work to minimum .00275", maximum .003" for the rods. Mains .003" to .0035" except No.7. white metal which is kept under .002". I have taken the liberty of letting Mr.Clarke read your memo and he expressed his appreciation of your fine memo. GWH.{George W. Hancock - Head Chateauroux} | ||