THE MOTOR WORLD

New Zealand Times, Volume XLII, Issue 9622, 30 March 1917, Page 8

THE MOTOR WORLD

LAND AND SEA NOTES CARE OF BEARINGS ON CARS. Without ball or roller hearings the motor car would be a sadly crippled vehicle. It is safe to say that you know less about them than any other important mechanical feature of the car. and this perhaps is the best testimonial of their serviceability, writes an expert in "Motor Life." You are familiar with the carburetter because it occasionally gives trouble; you can change the tires because you frequently have to, but you overlook the importance of the bearings because they are well behaved. You know that there are two kinds of beannßa —ID© plain buanng aiDd th© antifriction bearing. Tne piain bearing Das been used for years, you are familiar with it in machines of all kinds, and you naie seen it on the wheels ot the big loco motives. If it is good enough tor o steam locomotive why is it not satisfyTory for use in any part of the aUts mobile f . ‘ , , , It vou have ever noticed how careful he engineer is to oil tneso bearings at frequent intervals you have partly .answered the question. Uouid you like to stop every few hours and lubricate the front and rear wheel axles? That is what you would have to do, because plain bearings demand constant lubrication This is because, the rotating shaft does not bear directly against the soft bearing motai, but is separated from it by a thin film of oil, which must be constantly maintained in order to keep tho metal from wearing away rapidly. The crankshaft bearings are of this type amd vou know that in suite of the fact that they are constantly automatically lubricated, they wear out rapidly and allow play enough for knocks ana thumps to develop in the engine. ■ The second kind of bearing is the antifriction type, in which tho shaft is in rolling contact with the bearing, and in which friction is greatly reduced. Anti-friction bearings are indispensable in the transmission and the differential. In the transmission they perform the important function of keeping the shafts in use so that the gears slide smoothly in and out of mesh and mm without noise. In the differential they have an added duty to perform. Power from the engine is' transmitted to the rear axle by means of a driving pinion. The pressure between the teeth of the pinion and the large gear with which it meshes gives the pinion a tendency to climb on the teeth of the gear, and the bearing must take all the strain of keeping it in place. . IVith the exception of the tapered rol-ler-bearing, anti-friction bearings are not adjustable, and require replacement or regrindimg when worn out. Because of the important positions which they occupy in the car it is imperative that replacement be made as soon as wear has become evident, but if the car has been properly equipped the bearings will last several seasons. Occasional inspection is necessary, and, of course, any noise which originates in the bearings demands immediate attention.

There appears to he an erroneous belief that ball or roller bearings require no lubrication, and that they, operate just as well when dry. Such a Belief is far from the truth. Oil or grease is not only necessary as a lubricant, but also as a protective agent to prevent rust, and by surrounding the bearing to- prevent the entrance of .dust or grit. Only the best mineral oil or light grease should be used for this purpose. Contrary to the general opinion, graphite in grease, even though finely pulverised, causes the bearing to wear out mor© rapidly, and does not improve the running qualities of the bearing or reduce the friction. USING A SPANNER..

Good kit is very often spoilt by thoughtless or careless handling, and the brand of the beginner is generally to be found on the keys and .spanners contained in his tool roll. The actual destruction of kit is not in itself a very serious matter, as tools easily can be replaced, but it may be taken as certain that if the tools indicate bad usage, the nuts, etc., throughout the machine will be found in the same worn and mishandled condition. A good shifting spanner. if properly used, should last for years, but a few weeks in the hands of a tyro will reduce it to a nerve-shattered and weak-jointed wreck.

One of the most frequent misuses of large size shifting spanners is in the application of tho hammer. A shifting spanner should never be hammered except in' cases of dire necessity, and then great care should be taken that the jaws are tightly gripping the nut, otherwise the. stem of . the spanner will become "sprung,” so that it will refuse-to work easily, while in all probability the nut will be ruined.

If a hammer must be used the blows should be delivered to the handle of the spanner on the side opposite to the jaws—that is, with the bottom jaw of the, spanner pointing in the direction the nut is intended to turn. If the spanner is placed wrong way on and hammered, a few blows will probably suffice to ruin it, and at no time should pressure be applied to a shifting spanner in the wrong direction. * Shifting spanners are not intended for the purpose of removing or tightening valve caps, which must always be hammered. A special key is provided with every machine for this purpose, and not only does the use of a spanner spoil the cap, which is made of soft metal, but the spanner itself suffers. COMMAND OF THE AIR. "The Allies to-day,” states Patrick Y. Alexander, in a recent issue of "Flying.*’ “have complete superiority of the air. but it has been achieved at a tremendous expenditure of effort and money. We have not less than 500,000 persons in the British air service alone, including thousands of aviators, the mechanics and the manufacturers . of aeroplanes and aeronautic supplies. Aeroplanes can be seen in flocks anywhere. Every ship that leaves British ports is escorted by aeroplanes until it is quite a way beyond the Irish coast. We also have large airships which we expect will be superior to the very best Zeppelins. We have in use nt present hundreds of small dirigibles, less tiffin 300 ft long, equipped with aeroplane bodies instead of the usual nacelle. They are capable of staying in the air 50 hours and go at a speed of about 35 miles an hour. They are very useful in submarine warfare and coast defence.*’ A MOTOR TORPEDO-BOAT. Uncle Sam’s first motor torpedo boat had her first trial a few weeks ago, and despite conditions that were not the most favourable and that her motors were new and not worked out, she snowed a speed of 40.3 miles an hour O’er the Gardiner’s Bay measured mile course, which is the best speed ever shown by a motor boat of the cruiser type. This new craft is of the modified V type. According to the contract, she is to make 100 miles in three hours’ running and to exceed that speed in short spurts. This vessel, called the United States Toroedo Boat, is 50 feet long. 10 feet 6 inches beam, and is driven by two eigbt-cyiinder Duesenberg engines of 400 horse power, each. She carri«» a 1-pounder gun and has an 18-inoh torpedo ’ tube and on her trial earned a torpedo in the tube. . AMPHIBIOUS CRAFT. Several reports have been received of craft equipped with motors and capable of travelling on ice and water at excessive speeds, particularly on the ice. says the “New York Herald,” These

are in reality motor scooters, and, of both the sail. and motor variety, they afford (treat sport without the danger that is generally credited to ice yachts. In the motor scooter an aerial propeller is used, and in several instances the motors used to drive them were taken from automobiles and served their purpose admirably. In one case several motors from Ford cars were to be used in a one-design class of motor scooters and speeds of fifty miles an hour are expected by the enthusiasts, who intend fo build these craft. •