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 suitability of an American construction method for roll rod and shock damper levers and links.
| Identifier | ExFiles\Box 151\2\ scan0298 | |
| Date | 5th October 1936 | |
| To E. {Mr Elliott - Chief Engineer} c. to By. {R.W. Bailey - Chief Engineer} c. to Da. {Bernard Day - Chassis Design} X42 Hs {Lord Ernest Hives - Chair} /Les.5/KW.5.10.36. American Construction for Roll Rod and Shock Damper Levers and Links. Attached are a few preliminary results of tests which have been done to investigate the suitability of shock damper and roll rod levers being pressed on to their shafts and connected to the road wheel by an unlubricated rubber link. This construction, which is almost universally used in America, is an obvious saving in both weight and cost. The results up to the present show that such a construction has certain difficulties which were not initially apparent. Attachment of levers to Shafts. The earlier Delco shock dampers had a knurled shaft, hardened and pressed into a soft lever. However, the later Delco dampers have cut serrations on the shaft and in the lever, both are case-hardened and finally the shaft is driven into the lever. From Hs {Lord Ernest Hives - Chair} /WB. {Mr Brazier / Mr Bell} 4/JH.25.8.36 it can be seen that only a relatively small torque is required to cause the mild steel lever Ex.22113 to fidget on a mild steel shaft .010" interference fit before knurling. There is a similar lever pressed on to the roll rod fitted to 6-B-IV which is now running in France. As it is very unlikely that the Delco method for lever to shaft attachment is anything but the cheapest satisfactory method, it appears that we cannot hope to have freedom from trouble until case-hardened serrations are used for similar duties. | ||