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).
Cause of rattles in rear dampers due to bearing slackness and proposing design solutions.
| Identifier | ExFiles\Box 131\4\ scan0080 | |
| Date | 5th March 1937 | |
| 1113. Sg.{Arthur F. Sidgreaves - MD} from Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} Hs.{Lord Ernest Hives - Chair} E.{Mr Elliott - Chief Engineer} By.{R.W. Bailey - Chief Engineer} Rm.{William Robotham - Chief Engineer} Kingsbury. Rm{William Robotham - Chief Engineer}/GWH{George W. Hancock - Head Chateauroux}9/R.5.3.37. P.111 - REAR DAMPERS. The reason why I stated in my report that we should have trouble with the dampers after 10,000 miles was because it has already started. In investigating damper troubles, the rattle from slack bearings (slack bearings is really a wrong definition as a wear of .001" on the dia. causes the rattle), is caused by this small amount of clearance, due to the design of the damper. It comes about when actually the damper is doing no work, and is caused by the bearing being free of load one second, then coming on load. We blamed the Works for bad machining for a considerable time as the cause of the trouble. This no longer holds good, the dampers are being turned out 100%. It takes on an average 4000 to 10,000 miles to produce the slight amount of slackness in the bearings which causes the rattle. The car being used chiefly for town work shows up this fault, the 30 m.p.h. limit being the cause. The fault will still exist until either the bearing material is altered, or the design made so that a constant load is maintained on the bearing. Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} | ||