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).
Improvements and alternatives for Phantom III big end bearings and connecting rods.
| Identifier | ExFiles\Box 93\1\ scan0127 | |
| Date | 2nd February 1937 | |
| 314 Hs.{Lord Ernest Hives - Chair} from Rm.{William Robotham - Chief Engineer} c. to E.{Mr Elliott - Chief Engineer} c. to By.{R.W. Bailey - Chief Engineer} c. to Da.{Bernard Day - Chassis Design} Rm{William Robotham - Chief Engineer}4/R.2.2.37. P.III CONNECTING RODS. We have been concerned for some little time about the P.III big end bearings. The one hope of improvement to the standard car, which we have fitted to 35-EX, is connecting rods lined with Z.3 white metal. Further tests which have since been carried out have shown that the improvement with this alloy, compared with our standard alloy, is only likely to be a very small percentage. This being so, it is quite clear that for Continental conditions we are going to be involved in serious service costs with our rods. The alternative we have going forward is the strap type rod with the solid R.R. alloy bush. This gives indications of being satisfactory, but it is one of those un-mechanical set-ups which one can only consider for production after an enormous amount of experimental running and we should be very reluctant to recommend it for production even if it completed two 15,000 miles tests satisfactorily. In view of this fact we asked Rm{William Robotham - Chief Engineer}/Smth to look into the possibility of using articulated rods. We appreciate that a lot of work was carried out on these on our war time aero engine, and that there may be many disadvantages with them with which we are not entirely familiar. The advantages as we see them are, that we can use a plain R.R. tin alloy bush, which has proved itself to be reasonably satisfactory on our engines with proper lubrication, and that a material saving might be expected in the cost of the rods, which, at the moment, are fantastically high. | ||