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 analysis and comparison of a Humber car to identify areas for weight reduction.
| Identifier | ExFiles\Box 132\2\ scan0056 | |
| Date | 1st August 1939 | |
| Handwritten: Rm{William Robotham - Chief Engineer}'s copy Handwritten: e in Weight file 11/5 By.{R.W. Bailey - Chief Engineer} from Rm.{William Robotham - Chief Engineer} c. Da{Bernard Day - Chassis Design}/Ev.{Ivan Evernden - coachwork} c. Da{Bernard Day - Chassis Design}/Hdy.{William Hardy} c. Da{Bernard Day - Chassis Design}/Jnr.{Charles L. Jenner} Rm{William Robotham - Chief Engineer}9/R.1.8.39. WEIGHT ANALYSIS HUMBER CAR. You will by now have received a copy of the weight analysis of the Humber car, and we attach a brief summary of how we arrive at this. The object of these weight analyses is to see where we are heavier than other people, with a view to getting down our weights. A summary of the Humber weight shows that when compared with this chassis, and, generally speaking, compared with any other chassis, our major components are, relatively, light, i.e., the engine, gearbox and axle. The weight of our front suspension comes out almost the same as theirs. One would expect it to be somewhat lighter, as leaf springs are heavier than coil springs, but, on the other hand we know that they are strong enough to deal with 5¼-litre engines. The sections where we are really disproportionately heavier than the Humber are as follows:- Brakes, Frame, Steering, Exhaust System, wheels and tyres, chassis electrical and body. BRAKES. Operating Mechanism and drum, which accounts for no less than 70 lbs. 40 lbs of this is operating mechanism, which, of course, includes the servo which will disappear on the junior car. When the servo disappears the customers will not so easily be able to abuse the brakes. There is no doubt that we can get some weight off the B-V system if it is considered from the angle of the ordinary user as opposed to intense testing. FRAME. The object of the 'Ripplet' is to bring the front wheels back to the dashboard and enable a lighter frame to be used. We consider that the Humber frame is too light. The B-V frame, however, is obviously too heavy for a 6-cyl. engine, and on the 'Ripplet' this figure must be reduced considerably. | ||