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).
Phantom springing complaints, focusing on leaf friction and its effect on ride comfort.
| Identifier | WestWitteringFiles\S\September1928-October1928\ Scan023 | |
| Date | 27th August 1928 | |
| re PHANTOM SPRINGING COMPLAINTS. We have realized for a long time past that one of the most important factors affecting comfort in riding is leaf friction. We know from every-day experience that after springs have been in use for a considerable time, the leaf friction increases enormously and results in hard and uncomfortable riding, even when all external friction (Hartfords or Hydraulics) is removed. In numerous cases we have made an indisput-ably marked improvement by greasing the springs in position but we realize that this improvement is not lasting, and that even when the gaiters are filled with engine oil the springs gradually revert to the state they were in before, partly as a result of rust and corrosion and failure of the oil film, ultimately resulting in a form of seizure or roughening of the plates where they bed hardest, this being particularly noticeable on the Firth spring the majority of which have not such a good "bedding" area as the Woodhead spring. When we have observed springs, (in complaint cases), to bed badly, i.e. on a few high places, we have in a number of cases improved the bedding by light filing and then hand polished the ends of the plates, and this again has resulted in a definite im-provement in the riding. It is interesting to note that the friction of a spring which has become very stiff is consider-ably in excess of that of Hartfords set to 40 or more pounds, because with a well lubricated spring and Hartfords at 40 lbs. a car can be swayed and bounced by hand, whereas we have experienced many cases when it is practically impossible to bounce by hand even with the Hartfords disconnected, whereas, after bedding and greasing the same springs the car can be easily bounced by hand and the improvement in comfort and reduction of body rattles is most marked. Incidentally we almost always find a Hartford setting of about 40 lbs in conjunction with well greased springs to give the best all round results, and this is our observation based on actual trials of a very large number of cars, but never do we find riding so good if the spring friction is considerable even when external damping is slacked off. CONT'D.{John DeLooze - Company Secretary} | ||