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).
The investigation of lightening short frame gussets, including torsion test results for a Silver Dawn frame.
| Identifier | ExFiles\Box 113\5\ scan0119 | |
| Date | 8th March 1940 | |
| 100 To Ev.{Ivan Evernden - coachwork} from Rm{William Robotham - Chief Engineer}/Clm.{D. D. Clapham} C. Lee. Rm{William Robotham - Chief Engineer}/Clm.{D. D. Clapham}5/MH.{M. Huckerby}8.3.40. SHORT FRAME GUSSET. We have investigated the possibility of lightening the short gussets on rationalised frames, and have found that this can be done without weakening the frame torsionally. There are four of these short gussets per frame, two towards the front, and two towards the rear. They are in the same thickness material as the frame and have large lightening holes in their vertical webs. On the frame tested they were in .092" material, and weighed altogether 11 1/4 lbs. They were removed and each one was replaced by two strips of angle steel, 1" x 1", also in .092" material. The attached sketch is a part plan of B.V. frame. In the case of the gussets A and B, the existing rivet holes in the top and bottom flanges were used so that the effect was the same as if we had merely cut away all the vertical web except 1" at the top and 1" at the bottom. In the case of the front gussets, however, we used the same rivet holes in the side members but connected the angle steel to where the long gussets run into the cruci-form as shown in ink on the Sketch. The total weight of the new pieces in .092" material was 5 3/4 lbs. including an extra piece to carry the battery support. The saving in weight was therefore 5 1/2 lbs. As the tests were carried out on a Silver Dawn frame the actual torsion figures are rather low, but they show the alteration produced by this modification satis-factorily. Torsion Figures. lbs.ft/degree. Front to Rear Dash to Rear Dash to Front. With standard short gussets 1010 1640 2630 With angle steel at the rear and none at the front 985 1590 2600 With angle steel front & rear 1020 1650 2680 Rm{William Robotham - Chief Engineer}/Clm.{D. D. Clapham} | ||