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 decisions for the use of stiffeners on the Rippletto frame assembly.
| Identifier | ExFiles\Box 118\1\ scan0245 | |
| Date | 26th April 1940 | |
| FILE SECRET Rm{William Robotham - Chief Engineer}/878 1-6-40 To Rm.{William Robotham - Chief Engineer} from Ev.{Ivan Evernden - coachwork} c. to Rm{William Robotham - Chief Engineer}/HH. 1022 Ev.{Ivan Evernden - coachwork}19/JH.26.4.40. re Rippletto Frame. We have examined the print of the Rippletto frame assembly, RF.757 and have reached a decision as to the use of stiffeners, the frame material being .064" thick. Only where it is almost certain that stiffeners will be needed have we asked for them at this stage. Body Brackets. All of these need a stiffener, and the suitable designs are shewn on PL.205 (sheets 1 and 2). The front and rear body brackets should be treated in a manner similar to that adopted for the others. Front Engine Mounting. We think that a .064 ins. thick stiffener should be put behind each of the rows of rivets attaching the engine mounting bracket to the frame gussets and front pan. Front Suspension Rebound Stop. A .064 sheet stiffener is called for. Battery Support. We think that the battery support channels at the front end should be extended as far as possible into the gusset. The rivet can remain unaltered. This increases the heel action of the joint, and throws direct tension into the gusset webs. In all of these stiffeners, a certain principal of design should be adopted, as far as possible there should be an area of stiffener around the rivet not less than twice the diameter, and spot welds should be arranged in a manner around each rivet. This latter causes the stiffener to reinforce the thin frame under loads which do not put tension in the rivet e.g. the lower ends of the body brackets. Having dealt with some of the body brackets on | ||