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).
Temporary modification to a pump switch to prevent tracking.
| Identifier | ExFiles\Box 168a\2\ img295 | |
| Date | 20th April 1937 | |
| 6139 LOST CHASSIS. RE: SWITCH FOR TASTING EACH SIDE OF THE PUMP. As a result of Rm{William Robotham - Chief Engineer}/Vat's visit to Messrs. Lucas, it has been arranged that the corners of the central bar of the switch are being removed, with the object of trying to prevent tracking occurring. This as a temporary expedient will justify us carrying on with the present type of switch until such times as Messrs. Lucas are able to give us either a switch following the design of our own which was submitted to them or an improved switch with large air gaps. Personally, I would prefer our own switch which should be capable of being produced as cheaply as the switch which we are using. This will, however, take a little time in order to prepare tools if it were decided upon. The Stores will have to return all the switches to Messrs. Lucas, and this will apply to any switches which are at the various Depots - will Hd.{Mr Hayward/Mr Huddy} kindly arrange to have these returned, so that the milling away of the corners of the central bar can be carried out, as this appears to be a sufficient safeguard for its temporary use as Rm{William Robotham - Chief Engineer}/Vat. has carried out a large number of switch operations on a switch modified in this manner without failure. By HY.{Tom Haldenby - Plant Engineer} | ||