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 bonnet shutters for the P.2 model.
| Identifier | WestWitteringFiles\V\March1931-September1931\ Scan282 | |
| Date | 26th June 1931 | |
| AJL TO HS.{Lord Ernest Hives - Chair} FROM EV.{Ivan Evernden - coachwork} COPY TO BY.{R.W. Bailey - Chief Engineer} SG.{Arthur F. Sidgreaves - MD} ORIGINAL BONNET SHUTTERS. X1085. X7260. 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 thiner 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" is to use a knob as on the sample which you shewed 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 improv- if the radius at the corners were increased. We suggest that you try a radius of .750.ins. On the model which we saw we noticed that you had used the 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 that 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. In the new thick metal bonnet it may be different. Also we suggest that you use the riveting sent to you for the thick bonnet, N.Sch.3294. so reducing the rivets to eight per shutter. We are not certain whether we should be very happy with steel flaps in the aluminium panel, as we still do have a few polished bonnets and there is also the question of the prevention of rust. This our coachbuilders could not cure on steel wings. EV.{Ivan Evernden - coachwork} | ||