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).
Tests on modified cams to reduce the operational noise of a Watford EW6 Magneto.
| Identifier | WestWitteringFiles\R\2December1927-February1928\ Scan053 | |
| Date | 13th December 1927 | |
| To R.{Sir Henry Royce} from EFC. c. EJ. E.{Mr Elliott - Chief Engineer} c. Da.{Bernard Day - Chassis Design} Ey. c. ROY.{Sir Henry Royce} WATFORD EW6 MAGNETO. We are pursuing the question of reducing the noisiness of the make and break by using modified cams. We have already had some modified cams from Messrs. Norths and we expect some more. There was some evidence of reduced noise due to an easier make, but unfortunately the experimental cams which they sent were not right as regards timing, and we hope to receive further ones. A test we shall be making purely on contact breaker noise without the magneto functioning electrically is the reversal of the special cams which are easier on the make than the break, to see if we can arrive at whether the make is more noisy than the break, or vice versa. We have in the meanwhile received two further machines of this type Nos.100080/1. We are not quite clear at the moment whether Messrs. Norths consider they have fitted these with cams modified in accordance with our requirements or not. The first of these two has been on production tested (that means tested in accordance with our tentative specification of production test for use when these magnetos come through normally on production) with a satisfactory result as regards high and low speed running, range, etc. etc. and this machine is the one which has been put on your chassis 14-EX. But we regret that the noisiness does not seem to be very much improved over the standard. No.100081 has not yet been subject to any tests. Referring to this matter of cam | ||