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).
Comparing different design and supply schemes for Jackall rams and distributor boxes.
| Identifier | ExFiles\Box 140\2\ scan0146 | |
| Date | 13th February 1939 | |
| - 2 - Messrs.Rolls-Royce Ltd. 13th February, 1939 (2) To supply the current design of Jackall rams and distributor box. (3) To supply our latest design of rams and distributor box; details and trial set of which you now have in your possession. If Scheme (1) is continued, there will be an increased danger of bad workmanship and faulty material which may or may not appear until the system has been in use for some time and, in the case of a failure, we shall not be able to hold Shelleys responsible for any rectifications which, in turn, will not encourage them to be careful. You would, however, be utilising a design of distributor box and jack ram which has been in use on your cars over a considerable period. Scheme (S) will provide a design of distributor box and jack ram which has been in large production by Messrs. S. Smith & Sons for some time, but the accommodation of this design would necessitate the utilisation of single stage rams or two stage rams of a length so far never produced. The two stage design would also call for a clearance for an outside tension spring which would necessitate a very considerable alteration to your attaching brackets as well as a reduction of ground clearance. The distributor box could be accommodated, however, but it would require an entirely different type of mounting bracket and floor board cover. Scheme (3) employing our latest type distributor box and two stage jack rams would call for a very small alteration to the attaching brackets and would not involve the scrapping of the dies or patterns already in existence for the attaching brackets. Further, the dimensions of the rams in this case would not affect the head-room or ground clearance. Against this scheme must be considered the -contd- | ||