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).
Material choices and hardness for Delco shock absorber pads.
| Identifier | ExFiles\Box 56\1\ Scan082 | |
| Date | 3rd March 1931 | |
| To R. {Sir Henry Royce} From Hs {Lord Ernest Hives - Chair} /Rn. {Mr Robinson} c. to Da {Bernard Day - Chassis Design} /Hdy. {William Hardy} c. to By. {R.W. Bailey - Chief Engineer} c. to Sg. {Arthur F. Sidgreaves - MD} c. to Wor. {Arthur Wormald - General Works Manager} c. to E. {Mr Elliott - Chief Engineer} SHOCK DAMPERS. With reference to RL/M24.2.31. We note that you refer to Kelmet pads in the Delco shock absorber piston and axle connections. The dampers we have here have these parts made in steel, copper plated, which we think may have confused you. We understand from Hs. {Lord Ernest Hives - Chair} that Delco's copper plate the parts in order to get a better wearing surface as it allows the part to work harden before it picks up. We have tried copper plating from time to time for this purpose but have not had much success with it. We are testing out these pads in Nitro Alloy steel as we think that they have a hard time and have already shewn signs of wear on our tests, even in case hardened nickel steel, after some 50 hours running on the bump. Fortunately, the axle connections we have here have spring loaded balls in the same way as we have. We hope these parts were not omitted in the set we sent to you. The Rockwell hardness of the pads on the Delco shock absorber piston was 54 but we made our pads 60. Nitro Steel will, of course, be harder than this. Hs {Lord Ernest Hives - Chair} /Rn. {Mr Robinson} | ||