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 of a rivetless aluminium bonnet for the 20/25 model, proposing increased plate thickness and alternative materials.
| Identifier | ExFiles\Box 119\4\ scan0016 | |
| Date | 23th June 1931 | |
| X385 BY.{R.W. Bailey - Chief Engineer} FROM DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} DA{Bernard Day - Chassis Design}/EV{Ivan Evernden - coachwork}2/M23.6.31. Copy to SG.{Arthur F. Sidgreaves - MD} HS.{Lord Ernest Hives - Chair} re. BONNETS. X. 7260 X. 5260 X. 385. We have already outlined to you a means of building up a steel bonnet for the 20/25, using electric spot welding. We are now sending you N. scheme 3294, shewing a bonnet in aluminium which is rivetless. We have drawn it form N. 2. series P. 2. The idea is to so treat the hinges as to conceal the rivets, and to abolish all stiffeners to the side panel by increasing the plate thickness to .104 or even .116 or .125 Flip flap shutters are used fitted using 8 rivets each, and we suggest that these might be tried as countersinks now the material thickness is so much greater. As an alternative to the Ferodo bearing strip we suggest trying rubber, as it should prove quieter and less likely to wear into the aluminium panel. We would like a bonnet to this design fitted to a car and tested for stiffness and wear, as well as appearance. DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} | ||