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).
Various tests to reduce shake and stiffen the scuttle and dashboard structure.
| Identifier | ExFiles\Box 117\3\ scan0026 | |
| Date | 6th May 1940 | |
| -3- Strip No.9 is a record of the car on the bumper rig in the same condition structurally as when last tried on the road i.e., strip record No.8. It will be seen that the amplitude of the shake is about the same in both cases. Strip No.10 was with the diagonal stays fitted forward from the dashboard to the sides of the frame, and during the test we tried the dashboard mounting both solid and free, but there was no decrease in amplitude. The first sign of improvement was effected by removing the roll-bar, the difference being shown between strips 10 and 11. In our first trials on the road, we had tried the effect of removing the roll-bar, but apparently the scuttle structure was such that it showed no apparent improvement at this stage. In test 12, we tried the effect of bolting the dashboard solid with one mounting facing forward, strengthening the corners at the base of the dash at the same time. The results of this however increased the movement at the scuttle rail slightly, we can understand this after watching the scuttle and dash shivering when the former is free at the base. We now came to the conclusion that no matter how rigid we held the dashboard, it was having small effect on the scuttle at the instrument board, and that it would be necessary to build up some strength into the scuttle at this point. We therefore stiffened up the body bottom side, opposite the first body bracket with flat plate, and angle brackets set at right angles on to the chassis frame, a supporting bracket was also fixed underneath the body sill to the under side of the frame, see sketch. We next fixed stiffening plates into the scuttle rail, and bolted vertical tubular stays up the sides of the scuttle from the body side to the stiffening plates in the scuttle. A second tubular stay was welded to the vertical section and taken to the centre of the scuttle, where, to enable us to bolt rigidly, we had inserted a flat steel plate 3/16" thick, between the scuttle rail and a scuttle bracing rail. | ||