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 criticisms and proposed changes for a standard rear apron.
| Identifier | WestWitteringFiles\V\March1931-September1931\ Scan043 | |
| Date | 13th March 1931 | |
| FROM DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} C. to SG.{Arthur F. Sidgreaves - MD} HS.{Lord Ernest Hives - Chair} ORIGINAL P. 2. REAR APRON. DA{Bernard Day - Chassis Design}/EV{Ivan Evernden - coachwork}1/M13.3.31. x4531. Regarding Sch. 1440. sheets 1. 2. & 3., which were prepared from our N. sch. 3032., we offer the following criticisms on your layout, and return herewith the prints on which we have made certain sketches: Since SG.{Arthur F. Sidgreaves - MD} asks that this apron may be made as a standard fitting, and therefore suitable for all lengths of body we propose that you make the apron long as indicated, and have an instruction that the coachbuilder cuts it off to suit the body, and wires the edge. This he is quite able to do. The plan view should shew the extension of the wing in the form of a valance running up to the rear horn. It will be necessary for the valance to have transverse louvres in it at intervals to permit the heat and any gases which may collect to escape. It may be found that it is preferable that the central vent should spill on the outside of the valance instead of underneath it although America distinctly say it must spill underneath. If the former is the case the hump on the apron could be lower. The design is incomplete inasmuch as in the space between the petrol tank and the rear cross/member Barker's and other coachbuilders fit a toolbox which is accessible from the top of the apron. We think that our design should do this, and a toolbox on the lines of the one we designed some time ago for the runningboard position should be fitted in the apron at this point. Since there is now some doubt as to whether we shall wish to go ahead with a centrally vented tank we think the design of the apron should also be made suitable for the present standard petrol tank in two types - one for use with no luggage grid, and one for use with the new type 4. grid. The 2 aprons will be almost identical. We suggest that in order to reduce the size of the hump over the present K.{Mr Kilner} S. gauge fitting the aluminium cover which is fitted to the union piece, and which has a pear like form, can be with advantage omitted where an apron is used. The two together make the former redundant. We regret that we have not time to set out these owing to pressure of work on J.{Mr Johnson W.M.} 3., and we shall be glad to receive prints of your revised scheme. DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork} | ||