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).
Supply and bench testing of various spring and brush combinations for chassis.
| Identifier | ExFiles\Box 35\1\ scan 041 | |
| Date | 10th November 1919 guessed | |
| -2- Contd. On making inquiries of the Order Office we find that springs F.7180 are delivered in sufficient numbers for 1,000 chassis, and that brushes G.3901 in C.M. quality are delivered in sufficient quantity for 500 chassis (2 sets per chassis, one set a spare). We have now carried out the bench test of the strongest springs, under extra heavy load conditions, of the combination of C.M. brushes (as present standard) with the 10 lb. springs N.1760, and we have found this combination quite satisfactory. We have not, so far, asked the Order Office to put on order any more of the N.1760 springs, but we will do so immediately if you say that this should be done after considering the result of the above examination, together with the result of our test. Ultimately Mr. Royce, of course, desires to use springs of this 10 lb. strength together with brushes of C.M.3 quality. This combination, we take it, will have to be tested out on the 10,000 mile test before being standardised although it has stood up well on the bench test under extra heavy load conditions. Mechanical friction of the C.M.3 brushes will be less than with C.M. under the same spring pressure, and it may be that for this reason the amount of wear even with these softer brushes may be less than with the C.M. type. EFC. | ||