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).
Weight comparison sheet for various 1-40/50 model brake drum assemblies and their components.
| Identifier | ExFiles\Box 12\5\ 05-page313 | |
| Date | 1st November 1931 | |
| X7360 1-40/50 Brake Drum Complete Weight. Nov. 1931. X4612. Weight of complete Assembly on Hub Shell. Lake and Elliott lines alum Finish. G79546-7 complete with back plate, hub etc., = 49 lb. 4ozs. Lake and Elliot solid Drums complete etc., = 52 lb. 12ozs. R.R. Cast Iron solid complete (less .100 diameter to be machined out of bore. = 57 lb. High Carbon Steel complete. = 53 lb. 8ozs. R.R. cast Iron lined Alum finish complete less .060 diameter out of bore = 49 lb. 8ozs. 40% stiffer Standard Drum G79012 complete = 49 lb. EX Standard Drum G76123 complete = 44lb. 6ozs. 1-40/50 Front Drums complete. Lake and Elliot lines alum finish G79541-2 = 32lb. R.R. Cast Iron lines alum finish. =32 lb. 4ozs. High carbon steel = 33lb. 12ozs, Standard. G78823 = 27lb. 7ozs. Total Increase in car weight due To ribbed drums Front = 12lbs. 10ozs. Rear = 7lbs. 8ozs. ---------------- 20lbs. 2ozs. Front Drum Weights. End Plate. = 8lb. 10ozs. R.R. Cast iron lines and alum finish = 71b. 8ozs. R.R. Cast Iron solid Drum = 10lb. 6ozs. Studs and Nuts = 4ozs. | ||