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).
Potential weight reduction strategies for the 40/50 chassis.
| Identifier | ExFiles\Box 18\1\ Scan066 | |
| Date | 5th July 1934 | |
| X 7840 To Sg.{Arthur F. Sidgreaves - MD} To Mr. H's. To Mr. R.{Sir Henry Royce} To Mr. D.{John DeLooze - Company Secretary} To Mr. Ry. Dx. P. to LV. Hs{Lord Ernest Hives - Chair}/Gry.{Shadwell Grylls}10/KM.S.7.34. Re Weights - 40/50. We have been looking into how we can reduce the weight of the 40/50 chassis. We are just about to add 19 lbs. due to the synchromesh 2nd speed gearbox. (1) The present gearbox and servo change speed and 16 lbs. of clutch pit weigh 201 lbs. The synchro 2nd box + 220 " The Vulture box with servo and change speed but no clutch pit 127 " By using therefore the Vulture box we should save 55 lbs. instead of adding 19. (2) If we adopt the H.Sch.3561 clutch fitted to 27-HM{Capt. W. Hallam - Head Repairs} and 30-HL we can lighten this to ls.S6D and save 20 lbs. (3) By using magnesium castings for the lower half crankcase, timing case, gearbox and clutch pit we can save 30 lbs. (4) The Vulture front axle which has the smaller brake drum hub of 27 Ps.in. brake lining would save 54 lbs. (5) The Vulture rear axle fitted with 40/50 brake drums would save about 40 lbs. It is seen therefore that a total weight reduction of 200 lbs. could be effected but that design modifications are required and experimental work before it could be utilised. The SpectreCodename for Phantom III chassis incorporates the majority of these features. We do not therefore think it worth while fitting them to the Phantom as the customer will benefit almost as soon on the SpectreCodename for Phantom III. Hs{Lord Ernest Hives - Chair}/H.Grylls. | ||