TRANSPORT TIPS FOR TRADESMEN.
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Particularly Addressed to Those Who Are -Replacing Horsed Vehicles by Motors, or Contemplating So Doing.
Double Licensing. . ,
As THE LAW now stands, a motor tractor can be registered either as a heavy motor vehicle or as a road loComotive, and there are certain circumstances under which it is well worth the while of the owner to get it licensed under both categories. When used as a heavy motor, it may travel at the legal speed of five miles an hour, but is only permitted to draw one trailer, which in practice allows of a total useful load of about five or six tons. As a road locomotive it may not travel anywhere at a speed exceeding four miles an hour and, in towns, the speed may be restricted to two miles an hour. On the other hand, it may draw two or three trailers with an aggregate paying load only limited by its tractive power. In hilly country, particularly if roads are bad, the load contained in the one trailer permissible behind the motor tractor is just about as much as the engine can reasonably be asked to draw, but, in flat country, if roads are reasonably good, there is nothing but the law to prevent considerably bigger loads from being hauled. Thus, there may be occasions upon which the engine may be advantageously worked as a. motor vehicle and other occasions on which it will be better to work it as a road locomotive. Hence, some users have adopted this• practice known as double licensing, but there are others, particularly amongst those who -are new to motor transport., who have not realized the possibility of benefiting by so doing. ' The law on this subject was very clearly expounded on page 343 of the issue of The Commercial Motor dated May 18th last.
To Assist Rapid Loading.
It is impossible to over-emphasize the importance of making arrangements that will shorten the time taken in loading a motor vehicle. We must remember that we are dealing with a machine the capital cost of which is verymuch greater than that of an ordinary horse and cart. While loading is in progress, the capital invested in the vehicle is standing idle. Directly we begin to use motors it is specially important to cut out unnecessary terminal delays. There are many ways in which this can be done in different trades and; in the present instance, we will deal only with one example. Let us take the Case of barrels or packages that can be rolled along the ground. It is quite common to load such packages or barrels by arranging a sloping way up from the ground to the tail of the vehicle. It is much easier to push the barrels up an inclined plane of this kind than to lift them bodily to the required level Another plan is to keep them. ready for loading on a -raised platform at the same height as the vehicle body, getting them on to this platform by rolling them up a slope from ground level. Now, there are a good many cases in which the work of pushing the .barrels up hill can be done by the vehicle itself. Supposing the barrels to be placed on the ground in a yard, a lowered roadway can be arranged by cutting away the ground, allowing a sufficient width to take the vehicle and making the cut deeper as we gcl along so that a slope is. formed down which the vehicle can hack until, at the bottom of the slope, the platform of the vehicle is on a level with the yard where the barrels or other packages are kept. These may now be rolled or pushed into position on the vehicle without any
lifting effort being exerted. When the •vehicle is loaded, the engine in started up and the load is taken up to its ordinary level above the ground by the
power of the engine instead of by manual labour. There are many users who would have plenty of
room for applying this idea without making the slope, up which the vehicle has to travel, so stiff as to lead to trouble when the machine is fully loaded.
Supposing that space is limited and, consequently, the slope has to be very steep, the same principle can still be used if we employ a tractor and trailer. The trailer can be connected to the tractor through the wire rope gear, blocks being placed behind the tractor wheels to prevent it moving backwards. The trailer can then be permitted to run down the .slope and, when loaded, it can be pulled slowly up by the wire rope gear until it gets on to level ground behind the tractor and can be attached and drawn in the usual way. Similarly, if we have a self-contained, vehicle with a wire rope gear, the vehicle can be eased down the slope, the tackle being attached to a post or other object firmly fixed in the ground. When loaded, the vehicle can draw itself slowly up 'by winding in its wire rope, and can then proceed under power in the ordinary way. These plans are not put forward as being necessarily the best or even as being applicable in every case. They merely form instances of the application of a simple mechanical principle to the problem under consideration.
Air-cooled Engines.
Experience gained during the development of the aeroplane has had such an important bearing on the design of air-cooled engines that a number of motor vehicles of the lighter class fitted with. such engines are now appearin upon the market. In the past the air-cooled engine had not been uniformly successful, excepton motorcycles. The main difficulty is, of course, connected with the possibility of overheating. This is now reduced by the employment of more suitable materials than were available a little tune ago.
Nevertheless, we must remember that, even if the air-cooled engine is successful on light cars in private service, it does not necessarily follow that it will be equally successful on the lighter types of motorvan. These latter, as a rule, spend much of their time in districts where traffic is heavy,. and delays, therefore, frequent and speed comparatively slow. Moreover, while deliveries are being effected the engine is generally left running, with the car stationary. Thus, the conditions, as a whole, are each as to render overheating and its consequent troubles more probable than would be the case with the average private car. The nearer the conditions of use approach to those of the private car mainly employed in the country, the more likely is it that air-cooling would prove adequate on a light commercial vehicle. Provided it is efficient, it has, of course, the a.dvantage of eliminating the .expense of the water-circulating system and the troubles which may arise in connection with that system in very Cold.. weathenwhen the .effects of frost may be serious if the driver be careless or the attention given at the garage defective. At the moment,' the air-cooled motorcar can hardly be said to have emerged from the experimental stage. • Consequently, the adaptation of its chassis to van work is still a little speculative, though the experiment may be justified, provided the conditions or use are thoroughly favourable. The prospective motor user, knowing what these conditions are, will be better able to judge for himself whether he would be justified in endeavouring to save first cost by selecting chassis with air-cooled engines, to be fitteX, with light van bodies.