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).
Rear axle jacking tests for the Wraith II Scott Model No.2.
| Identifier | ExFiles\Box 139\1\ scan0266 | |
| Date | 18th September 1936 | |
| To Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls} x1044 1166 Hs{Lord Ernest Hives - Chair}/WB.{Mr Brazier/Mr Bell}3/KW.18.9.36. Rear Axle Jacking Tests. Wraith II - Scott Model No.2. With this, the second Scott Model, the axle casing was supported at the spring centres, the load suspended from the top of the banjo casing and a stiffening plate, SK.5010, fitted on the underside. This arrangement proved to be considerably stiffer than that used for the first model, although the first signs of permanent set were recorded at approximately the same load. After testing up to 6,000 lbs. to obtain a comparative bending movement to that obtained on the first model, the SK.5010 stiffening plate was removed, and the load reapplied in gradually increasing stages, and at 4,500 lbs., the structure collapsed. The load was further increased to 5,000 lbs. and the deflections and permanent sets measured. The comparative results (with and without the plate) are illustrated in Sheet 1 of the attached graphs. It should, however, be noted that the axle had already taken a permanent set of .088" before the plate was removed. Although the axle had reached buckling point - at the junction of the centre casing and the axle tubes - chalk testing did not reveal any cracks. Hs{Lord Ernest Hives - Chair}/W.Bell. W. Bell | ||