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, operation, and construction of flip-flap bonnet shutters for the P.2 model.
| Identifier | ExFiles\Box 12\7\ 07-page171 | |
| Date | 26th June 1931 | |
| To Hs.{Lord Ernest Hives - Chair} from Ev.{Ivan Evernden - coachwork} c. Bv. Sg.{Arthur F. Sidgreaves - MD} X7260 Evl/26.6.31. X.1085 X.7260 BONNET SHUTTERS. As we hope to standardise the flip-flap shutters for P.2, in time for Olympia, we are anxious to get the design correct as soon as possible. OPERATION. The facility of operation was thought to be a little difficult. We gave you a suggested spring, but it must be decided by test what spring pressure is needed. We suggest that you try a weaker spring, either by the use of thinner wire or with the same wire but having less initial set in the spring. In order to give greater leverage for opening we also suggest that the axis might be placed say .200 nearer the centre of the flap. This would call for no change in the design of the pieces. A third alternative now suggested by R.{Sir Henry Royce} is to use a knob as on the sample which you showed to us, the knob having the smallest dimensions possible. In this case the axis of hinging would be moved as far to the edge of the shutter as is possible. We would prefer to avoid the use of knobs if it is at all possible. CONSTRUCTION. It is suggested that the appearance would be improved if the radius at the corners were increased. We suggest that you try a radius of .150" On the model which we saw we noticed that you had usedthe sheet steel shutter and sheet steel fitting designed for the steel bonnet on an aluminium bonnet, and not the pieces we designed for the aluminium bonnet. We are going to ask you to tell us by phone on Monday whether you prefer to use these sheet metal pieces on an aluminium bonnet, as if so we might reconsider the design. In any case we suggest that ordinary rivet be used for the attachment of the fittings to the bonnet panel unless we can carry out a thorough test of the countersunk ones, as the latter so far have always given trouble in the .080 metal. | ||