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).
The benefits of chassisless, welded light-gauge steel car body construction versus traditional body-on-frame designs.
| Identifier | ExFiles\Box 117\1\ scan0089 | |
| Date | 22th October 1936 guessed | |
| 7. terior body lining stamped out of very light gauge steel, and a complete outer body shell stamped out of very light gauge steel, the interior shell being perhaps an inch smaller in overall dimensions than the exterior shell, these two shells then being welded together by this new projected welding process, which would leave no exterior scars, and these two shells then being attached to each other by the offsets in the stamping necessary for windows, doors, ventilators, etc. In visualizing the above described type of a body which would eliminate all present heavy steel reinforcement used throughout present automobile bodies, you would have in effect two boxes one within the other spaced perhaps one-half inch apart and welded rigidly together, thus providing the strongest possible structure with the least possible weight in which you automatically get air gap insulation, and in order for you to visualize the possible strength of such a structure may I suggest that you form up two very light panels of perhaps 35 gauge steel with side walls perhaps one-half inch in depth and then test and see how flexible these pans are, then weld the two together into a box or closed section, and you will be amazed at the rigidity. A little over two years ago, largely as a hobby, we built up a small chassisless automobile with the engine mounted in the rear. The body of this car was made up very much along the lines above described, and we have hammered it over a lot of rough roads and its absolute freedom from vibration, squeaks and groans has been a real joy. When a motor car body is supported on an independent chassis, it is just something carried on top of something, and it fights and resists every reaction of the chassis, whereas when you build up a boxlike body and fasten the axles directly to this body you then put the top of the body under compression and the bottom of it under tension. The result is that this body under these constant load conditions just seems to lose all of its swerving and fighting within itself, and doors lose their inclination to jump and rattle, even though the structure surrounding them is very much lighter than used in a body supported on an independent chassis; and these results have been proven out through millions and millions of miles of our bus experience and the principle was again proven in the small car mentioned above. There is still far too much weight in all motor vehicles, and you can prove this by going down and looking over any automobile junk or grave yard and observe the great number of parts which are still perfect in these totally worn out and discarded automobiles, which proves that many parts were far heavier than was necessary; and I predict that with additional experience and with the coming of the chassisless type automobile we are going to see radical weight reduction and greatly increased safety in our future cars. | ||