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).
Reduction and design of louvered bonnets for the 20/25 HP model.
| Identifier | ExFiles\Box 102\6\ scan0151 | |
| Date | 22th October 1935 | |
| x585 To BY.{R.W. Bailey - Chief Engineer} Copy to RHS. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Hn.{F. C. Honeyman - Retail orders} LR.{Mr Ellor} E/Ev.{Ivan Evernden - coachwork}1/MN.22.10.35. STEADMAN Re 20/25 H.P. Louvred Bonnet. You will see from a previous memo. written by E.{Mr Elliott - Chief Engineer} that we are endeavouring to reduce the number of different bonnets which are supplied to Coachbuilders for the 20/25 H.P., and have suggested two or three bonnets at the most. In the meantime to enable you to supply Sales with dummy louvres we have set out on LeC 4775 and LeC 4776 herewith side panels with 11º and 16º back end slope respectively, for both 6" and 9" overhang. We do not think it is necessary to cater for dummy louvres on the vertically shuttered bonnet with vertical back end, or for any of the peculiar combinations of vertical back ends with sloping louvres or vertical shutters with sloping louvres. We have discussed the question with Hn.{F. C. Honeyman - Retail orders} and he agrees in principle. The section of material used for the dummy louvre is that which was supplied to us by Sales, and it is fastened in a similar manner, namely, the rivet shank consists of a piece of aluminium wire passed through a hole in the strip and welded at the head. On both schemes we have shown alternative treatments, one of which is to space the louvres with a different pitch in different places, and theother is to move the flip-flap shutter so that the spacing may be uniform. We think that the former course would be the most practical. In the case of the 11º bonnet LeC 4775 and the 6" overhang, we suggest that in order to bring one louvre at the edge of the bonnet the last five louvres after the rear edge of the rearmost flip-flap shutter be closed together by an amount indicated. Unfortunately, in the case of the 16º bonnet LeC 4776,this same treatment is not possible, and we suggest that instead of the last louvre coming on the edge of the bonnet, one louvre should start with its forward edge in line almost with the beginning of the scuttle. It is desired to make a sample bonnet side panel and to have it properly painted and polished by Messrs.Sanderson & Holmes, so that it will be possible to examine the success of the scheme, and to send it if necessary to Sales for their approval before we treat any production bonnets. | ||