Rolls-Royce Archives
         « Prev  Box Series  Next »        

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).
Technical memo discussing the lengthening of bonnets for the 25 HP model.

Identifier  ExFiles\Box 102\6\  scan0127
Date  12th March 1931
  
COPY. X5260.

CX.{Major Len W. Cox - Advertising Manager} FROM DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork}

DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork}1/M.3. 12. 31. X5260

C. to SG.{Arthur F. Sidgreaves - MD} BY.{R.W. Bailey - Chief Engineer} HS.{Lord Ernest Hives - Chair} 25 HP. LONGER BONNETS.

This is to confirm our conversation of yesterday re. the above, when discussing the print of N.sch.3381. shewing the bonnet carried 3" over the dashboard and therefore lengthened altogether by 5.6" over our present production.

We think that if still more lengthening is required the 3" overhaul could be increased to 4" keeping the taper between the side panels of the bonnet the same. This would give the width over the side panels at the back as 36.250.

The effect would be to slightly involve the scuttle of 'C' steering cars, but would in a way enhance the effect on 'D' and 'E'. No further lengthening can be done on 'C' column cars without considering widening.

We do not like the proposal to supply a very long bonnet so that the coachbuilder can cut off to any length he desires because, firstly, we do not feel that we can rely on all our coachbuilders, secondly, even for us it would be a very difficult job to do, especially in the thick material we are proposing to use to avoid shewing the rivet heads, and also our hinge material is consistent. We have to reinforce the hinges at the bonnet ends. Furthermore, in the case of louvres we should not know where to stop them, and in the case of shutters we should not know where to put them to balance up the appearance. We ourselves are in favour of a moderate policy of the 3" proposed, but do not see any harm in an additional 1" being added.

You will no doubt keep us informed of what decisions are taken.

DA{Bernard Day - Chassis Design}/EV.{Ivan Evernden - coachwork}
  
  


Copyright Sustain 2025, All Rights Reserved.    whatever is rightly done, however humble, is noble
An unhandled error has occurred. Reload 🗙