HIGHER TECHNICS.
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By "The Inspector."
IWONDER if the impression left on mY mind after a fairly exhaustive examination of both Paris Salon and London Olympia exhibits has remained with others who have had the same opportunities? I came away from West Kensington with the conviction, received at Paris and now confirmed in London, that, for the first time, most of the biggest chassis and quite a few oft the smaller ones bear evidence of the application of very highly technical evolution. In previous years, 1. cannot remil. anything like so general a display of the adoption of means and devices that are obviously the result ot exhaustive technical analysis and development. Most manufacturers, it is true, had long ago thrown away ideas that were comparable to the use of rolled mildsteel channel-section girders for frame members, and they, too, had early learned the lesson of high-grade alloy steel and bronzes and other metallurgical fancies—at any rate they had a smattering of it. But, I believe my readers will not quarrel with me when I state that, with one or two very remarkable exceptions—such, for instance, as the followers of the Lanchester school—there was very little in the design of British touring-type chassis which showed evidence of planning from first principles.
At first hearing, this sounds a very sweeping statement to make, but one only has to recall a few examples of crudity of conception to realize that there is, at any rate, some justification in the charge. In how many cases, for instance, have we noticed the failure to co-ordinate the radial centres of propeller shaft, brake rods, torque bar and radius rods ? How seldom did we find provision made for the independent rise and fall of side springs? How frequently much-advertised and ill-named three-point suspensions were, in effect, nowhere near the objects aimed at? And what evidence generally was there of the true estimation of complicated and combined stresses and of effective means to take care of them?
I am not quarrelling so Much, however, with the actual mechanical devices, adopted as a result of trial and error, but rather with the way in which, devices have been proportioned and carried out. An example of the new way of looking at things occurs on the new Lanchester chassis. There is a certain cross member, in line with the pivot point of the cantilever rear springing, a tube of over 6 ins. in. diameter, I should imagine, and theoretically very, very thin, but on account of its section immensely
strong. sow, though this is ugly, it undoubtedly represents metal in the right place, compared, shall we say, with the old-fashioned channel-steel cross member. We now find deep square-section pull rods for brakes and the like, where-as no one until recently dreamed of anything but "round rod." Front axles are something more than fl-section girders, and some care is taken, too, of the complicated bending and twisting stresses which affect such a component.
It is quite evident that the very trying conditions of wartime production, its call for accuracy and particularly the opportunity to turn out the, best possible with but little regard for the cost of such excellence, has left' its very definite mark on the work of the designer to-day. I know of several cases, for instance, where designers are employing the elasticity of steel bar in a torsional sense for its springing properties. which surely is a n'ractice that would very rarely have been dreamed of in older days. More has been learned, and more of such learning. applied, concerning the employment of flat and alternatively curved thin plates and the means such construction affords of securing maximum strength with minimum., weight in certain circumstances. There are numerous other evidences that we are no longer so sadly tied by convention and that the man who cannot think beyond straight channel frames and plain, clumsy semi-elliptic spring S is going to be badly left. There has been little to be seen of. the effect of war experience on design as yet, but, in a year's time, we shall have many chassis that will be, in constructional and technical detail, if not necessarily in general arrangement, as. much in advance of recent methods as the magneto was ahead of tube ignition. And I claim that, particularly, the latest examples of big' engined " luxury " touring cars are evidence of what is going to spread to all classes of commercial vehicle design and not least to the industrial vehicle. Quite fully to appreciate what this means ;4.we must consider what would happen to the overtype steam wagon if we could turn the technical ability that produced the Hispano-Suiza or the Talbot-barracq on to its revised designs. It is all very well to say -the steam Wagon is the best thing for its job, but it is not. always designed by men with the same command of 'higher technics and there is no reason why it should not be. Higher technics do not necessarily imply higher cost. Very often it is just the other way.