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).
Engine vibration issues caused by the slipper drive on 40/50 and 20 HP chassis, proposing improved surface finishing.
| Identifier | ExFiles\Box 74\2\ scan0360 | |
| Date | 9th April 1923 | |
| X.4244 BY.{R.W. Bailey - Chief Engineer} c. to Hs.{Lord Ernest Hives - Chair} c. to Sft.{Mr Swift} EP{G. Eric Platford - Chief Quality Engineer}4/H9.4.23. RE. SLIPPER DRIVE FOR 40/50 AND 20 HP. CHASSIS. X.3439 X.4244. After investigating engine vibrations and making comparisons between different engines which vary, although in most cases only slightly, we have found that the only definite feature which we can handle to cause this slight variation, appears to be the variation in the working of the slipper drive. A slipper drive which is new does not appear to give as good results as one which has done a considerable amount of engine running, and the chief difference appears to be that the friction surfaces appear to become polished and more smooth in their action. It appears that the friction surface should be a much better finish than at present in order that as far as possible we are in a position to turn out engines, even when new, which run sweeter and do not require considerable running before the sweetness is attained. I suggest that instructions should be given for the surfaces against which the fibre rubs to be ground to a fine finish, if possible lapped or buffed and that the whole slipper drive should be built up and 'run in' so that the surfaces are actually burnished to each other. I also feel that final doping with 'oil dag' would give beneficial results. We are now making various tests in this direction but in the meantime I think the investigations have gone sufficiently far to establish the importance of the slipper drive surfaces being properly polished, and shall be glad if instructions can be given that this is carried out, and everything possible is done to obtain this finish in a new state. In order to obtain more smooth working of the 40/50 slipper drive, which is the worst culprit at present, we certainly advocate that the spigotting surface of the slipper flywheel would be whitemetalled in the same way as is the practice with the 20 HP. slipper flywheel. Ep.{G. Eric Platford - Chief Quality Engineer} | ||