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).
Technical memorandum discussing the correction and bushing of holes in leaf springs to prevent wear.
| Identifier | ExFiles\Box 54\3\ Scan098 | |
| Date | 29th January 1923 | |
| X. 2628 To BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} c. to Ws. c. to CJ. c. to Wor.{Arthur Wormald - General Works Manager} c. to Hs.{Lord Ernest Hives - Chair} c. to EP.{G. Eric Platford - Chief Quality Engineer} R7/M29.1.23. SPRINGS. X.2628. With reference to your BY9/P22.1.23., I certainly think that the holes in the top leaf of the springs should be corrected for diameter and alignment, by us. I think each spring should be clamped in a suitable jig, not placed on the axle, and the holes opened out under a suitable machine, to an exact dia. Ws. ought to produce a jig to suit this purpose, and we ought to have a drilling machine with two heads that can be set a convenient distance apart to enable us to do both holes - (such a machine is used for large connecting rods.) It may be necessary to correct the hole with a single pointed tool or a four lip drill, and afterwards ream for a press fit. I am not sure however whether we have not already arranged that the spring shall be bushed with flange bushes so as to increase the area. Such bushes might be case-hardened and have a loose bronze sleeve for the pin. We cannot believe that the loose bush is the cause of the wear unless it means that the soft steel of the spring and the brass bush are not happy together, whereas the case-hardened pin and a fixed bush in the spring-eye, would be. To prevent this wear we think that nothing but case-hardened steel faces should be used wherever possible; the reason being that copper or brass or even soft steel will get impregnated with grit, and so act as a lap. contd:- | ||