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).
Design specifications for brake straps, rear springs, wheel spokes, and the sourcing of alloy steels.
| Identifier | ExFiles\Box 180\M3\M3.3\ img002 | |
| Date | 29th August 1912 guessed | |
| -2- taper bore, and external collars, instead of stepped sections. The use of aluminium brake straps for the footbrake, as used in 49-GB, and generally machining the parts to lighter dimensions, except where there is any sudden change in the direction or intensity of the stresses. That the rear springs shall remain above the axle, but to be of the light thick plate type, with the lower plate split at the rear end, the axle being fitted with a three flange roller. Two security bolts in the ends of the plates. With reference to road wheels, it is thought that it would be better to continue with the Dunlop pattern wheels, but owing to the failure of spokes, to insist upon the spokes being made of Vanadium Chrome, or other high duty alloy steel, but they should be carefully heat treated, and thoroughly well tightened. Great care should be exercised in the chassis weight, and the duties of the Inspector should include the checking of the weight of each piece, that is, while being passed for dimensions and otherwise. To facilitate manufacture and leave ourselves less dependent upon outsiders, it was agreed that about 200 tons or more of various good alloy steels, suitable for drop forgings, for various parts, should be obtained from Messrs. Brown, Bayley's or other reliable people. That this material is to be held in hand at our Works so that it can be sent off to the drop forgers, or used for drop forgings made by our own plant, for the purpose of these cars, or for other urgent work that it may be found suitable. | ||