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).
The internal friction and damping characteristics of Firths and Woodheads road springs.
| Identifier | ExFiles\Box 54\3\ Scan124 | |
| Date | 8th July 1924 | |
| To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to BJ. c. to DA.{Bernard Day - Chassis Design} c. to E.{Mr Elliott - Chief Engineer} c. to BY.{R.W. Bailey - Chief Engineer} X2628 Hs{Lord Ernest Hives - Chair}5/LG18.7.24. FRICTION IN ROAD SPRINGS. X.2628 X.4429 X.9410 The question of internal friction of road springs was taken up at the time we started tests on Firths springs. Our first criticism of Firths springs was that when fitted to a car they had not sufficient internal damping; they gave one the impression of the thick leaf springs. In taking the springs apart it was found that there was less nip on the Firths springs compared with the Woodheads. Having in mind our experience with the thick leaf springs, we criticised Firths springs from the fact that they appeared to have less internal friction. Tests were made both at Firths and at Derby and it was found that by actually measuring the friction and gradually increasing and decreasing the load, the difference between Firths and Woodheads was negligible, if anything, Firths had slightly more friction. All the cars which have been tested are fitted with Woodheads make of rear springs. No cars have left the Works fitted with Firths springs at the rear. On the EAC.lll.cars, the front springs are Firths. We are carrying out tests measuring the actual friction in the rear springs which were fitted to 46-PK car. Hs.{Lord Ernest Hives - Chair} | ||