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).
Instructions for a series of experimental tests on battery ignition components.
| Identifier | WestWitteringFiles\Q\2April1927-June1927\ 16 | |
| Date | 1st April 1927 | |
| To R.{Sir Henry Royce} from EFC. c. BJ. E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} EY c. Wor.{Arthur Wormald - General Works Manager} Rg.{Mr Rowledge} ORIGINAL EFC1/T1.4.27. BATTERY IGNITION. X4652 X4021 There are a few further items for report. The following are now instructed to be made for experimental test:- (1) Three-part cam, i.e. cam with three flats to give three makes and breaks instead of six, each make period being of the same duration as previously. For correct comparison, i.e. to see if platinum points benefit by having longer time to cool down, this will be run at normal test speed and for double length of time, so as to perform the same number of breaks. In this connection it is noted that in running the present cam at half (or double) speed, we are changing two things - we are increasing the current at break which may affect the points adversely, but at the same time we are giving them longer time to cool which may make up for the first. Comparative results of tests both on platinum and tungsten points running at double and half speeds are now completed, and the results shew no material improvement or disadvantage with either, either way, i.e. the results are mainly similarly unsatisfactory. (2) Quicker break cam giving 40% increased rate of break on the same make ratio. This will be run at standard testing speed and the one difference will be the quicker rate of break. One feels that there must be an advantage in altering the magnitude of the current at break, other things being the same, but we are, as previously stated, doubtful whether there is much advantage in the quicker break, other things remaining the same. (3) Off-set rocker. It was hoped that this in itself would give a quicker break on a present standard cam, but this does not appear to do so to any useful degree. We are of the opinion, however, that a test should be made of it because it still contains one experimental modification from standard of an apparently desirable nature. Contd. | ||