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).
Comparison and proposal for revisions to various bonnet designs, discussing parts, weights, and production standards.
| Identifier | ExFiles\Box 119\4\ scan0118 | |
| Date | 21th September 1938 | |
| -3- Rm{William Robotham - Chief Engineer}/Std.1/WH.21.9.38. With regard to HPS.{Horace Percy Smith - Experimental Factory Mgr}2/VS.{J. Vickers}30.6.38, we would point out that a good deal of the information contained therein requires qualification. As regards numbers of parts it will be found that if the standard B.II bonnet LOP is considered and compared with B.50 LOP (includes bonnet, rest angles, rest plates etc. complete), the former has more pieces (total no.) more K pieces and more individual pieces (other than K parts) than the latter, so that mere unqualified figures as to numbers of parts do not convey much real information. It is difficult to see how the "side plates could be incorporated in the end stiffeners". As regards paragraph seven, only one endways location for end side plate is called for on the scheme. With regard to weights given in HPS.{Horace Percy Smith - Experimental Factory Mgr}2/VS.{J. Vickers}30.6.38, 1.B.50, 7.B.V. and 6.B.IV (B.II bonnet in steel) bonnets are not comparable since - (a) 6.B.IV bonnet is louvred which alters the stiffening of the side plate altogether. (b) Neither 6.B.IV bonnet nor 7.B.V. are acceptable as approaching production standard - it has been necessary to increase the gauge to .040 (19 SWG) and provide stiffeners (in an endeavour to overcome some of the defects of these bonnets) on 8.B.V. bonnet which weighs 6 1/2 lbs. Summarising, we consider that the B.50 Rover type bonnet scheme should be revised for B.III and B.50 to incorporate certain improvements and cost reductions which have already been discussed between DS/V.{VIENNA} and Rm{William Robotham - Chief Engineer}/Std., and which are made possible now that the B.III and B.50 radiators have vertical back edges to their shells - at the time when the scheme was first done the slope of the original B.50 shell precluded most of the proposed alterations. The revised bonnet should be detailed and we will arrange to fit bonnets of this type to 9.B.V, 10.B.V, 11.B.V and 2.B.50 chassis. Rm{William Robotham - Chief Engineer}/Std. | ||