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).
Mr. Royce's feedback on pivots, bracket fittings, and bolts, including a small diagram.
| Identifier | WestWitteringFiles\E\November1920\ Scan7 | |
| Date | 6th November 1920 | |
| To DA.{Bernard Day - Chassis Design} from E.{Mr Elliott - Chief Engineer} -2- EL/06/11/20 Contd. (4) Referring to the pivots for the centre of the rear springs, Mr. Royce agrees to the adoption of a flange on the pivot pin, but it should be fixed with two large bolts instead of four small ones so as to avoid a rectangular flange which overhangs the bottom edge of the frame. The pivot should be lightened out by a taper boring the inner end and the washer for the pivot retaining bolt should be made stronger and suitably chamfered on the outer edge. MACHINE The fitting for the cross member and pivot should be continued beyond the inner end of the pivot to avoid a weak spot in the cross member at this point, and to ease off the stress in the tubes. This can be provided without increasing the centre distance between the pivot and the cross member by cutting away the pivot bolt washer at one point. The tube for the cross member Mr. Royce remarks, might be reinforced near the ends. (5) Referring now to the bracket tubes and fittings, Mr. Royce says he does not understand the origin of the cheese headed clamping bolts shewn with snugs. He thinks this is not R.R. practice, and he would like the new square heads of the new type with chamfered corners used here. The thread should be the same diameter as the stem of the bolt so that the nut is not a small hexagon covering a large hole. Further Mr. Royce wishes you to use thin nuts locked by rivetting on these bracket bolts. (6) Referring to the forked fittings, Mr. Royce does not like cutting away the root of the fork for the purpose of getting the bolts in. He would like the bolt centred a little further out, as he thinks the problem in providing room for the bolt head is exactly the same as providing room for the nut, and it is not necessary to have a feature to prevent the bolt head turning. The bolt should be one having the new type of square head with chamfered corners, and a circular face only should be provided on the stamping for it. The bolt bosses on the stampings should be made equally long on each half and to the larger dimension shewn. The idea is generally not to attempt to prevent the bolts from turning, and to use a spanner on the head when it is desired to tighten them. (Contd.) | ||