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).
Unlocked piston pins and locking screw types for the 40/50 HP chassis.
| Identifier | WestWitteringFiles\C\February1919\ Scan20 | |
| Date | 28th February 1919 | |
| To BY.{R.W. Bailey - Chief Engineer} from E.{Mr Elliott - Chief Engineer} Copy to DA.{Bernard Day - Chassis Design} EH. RE CHASSIS PISTON PIN - 40/50 H.P. In reply to your memo BY1/P26219 raising the question of the unlocked piston pin in the aluminium piston confined endways by small steel rings, you have no doubt already received our memo E3/G28219 asking you to revert to the original type of piston pin locking screw with taper and thread in the piston pin and parallel fit in the piston pin boss. It is on record that there are thousands of piston pins free in both piston and connecting rod, running satisfactorily on aero engines, but of course a slight tap at low speed may not be noticeable, owing to the variety of other noises that these engines make. There have been no reports as regards excessive wear in the piston pin bosses. E.{Mr Elliott - Chief Engineer} | ||