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 of 'Myth' brake components and comparing them with Lockheed parts.
| Identifier | ExFiles\Box 110\1\ scan0023 | |
| Date | 28th October 1940 | |
| 1030 To Rm{William Robotham - Chief Engineer}/GB. c. to Rm.{William Robotham - Chief Engineer} c. to Ev.{Ivan Evernden - coachwork} Ev{Ivan Evernden - coachwork}/DB.{Donald Bastow - Suspensions}2/JH.28.10.40. 706 Weight of Myth Brakes. The weight of the carrier plates, cylinder and shoe assemblies quoted in Rm{William Robotham - Chief Engineer}/GB.1/ET.20.10.40. and referred to in Rm.{William Robotham - Chief Engineer}4/ML.23.10.40. was unfortunately given to Rm{William Robotham - Chief Engineer}/GB. in error, as it is the weight given to us by Lockheeds for 4 such assemblies for 11" brake drums, with the rather heavy Lockheed carrier plates which are .125 thick all over. Preliminary calculations from the schemes of front and rear brakes, now almost completed, show that this figure can be considerably reduced, a corrected table will be approximately as follows :- 2 front carrier plates, cylinder and shoe assemblies. 16 lbs. 2 rear carrier plates, cylinder and shoe assemblies. 16 1/2 lbs. 2 front drums and hubs combined. 24 1/2 lbs. 2 rear " " " 26 lbs. Pipes hoses and fittings. 4 lbs. C.I. master cylinder. 3 lbs. Handbrake control. 9 lbs. ___________ 98 3/4 lbs. In this connection it is interesting to note that the combined drums and hub assembly is about .3 lb. per drum heavier than the combined weights of hub and drum of the alternative construction of the type we use at present and that owing to the larger diameter of the pitch circle of the wheel bolts it enables a saving in wheel weight of approx. .75 lbs. per wheel to be obtained i.e. a nett gain of .45 lbs. per wheel. Our carrier plates save an appreciable amount of weight as compared with the Lockheed ones and in Cont'd.{John DeLooze - Company Secretary} | ||