Putnam's Automobile Handbook: The Care and Management of the Modern Motor-Car
CHAPTER XIII
SKIDDING MAY BE MINIMIZED
When you are out driving next time watch the cars ahead of you and notice how many of them have wobbly rear wheels. You can by this means tell fairly well who is a careful driver and whose car has been skidding about the streets and has brought up sharply against the curb, or car track, or rut, or some other obstruction over which the wheels would not slide, and which was sufficiently solid to give them a hard knock.
No man can appreciate what a skid means until he has had one and then, perhaps, he will not live to appreciate it. No amount of preaching seems to do any good. He must sow his wild auto-driving oats and learn from experience. Because of this, it is recommended that each driver who has not had a real skid yet, pick out a very broad and wet street paved with asphalt where there is no traffic in sight. Let him drive the car fifteen miles an hour up the middle of the street, then give the steering wheel a sharp turn to the left, at the same time applying the brakes. The resulting sensation of absolute helplessness will be remembered for an hour or two—at least. For those who wish to continue the lesson, try allowing some other driver to repeat the operation, while the experience seeker occupies the back seat.
Now the skid against the curb or other obstruction may not have demolished the wheel, but it left its mark in cracked spokes, or bent rim, or if the car was of a certain type of construction it may have bent the axle shaft itself. If the wobble is due to a bend in the rim, it wears the tires excessively and if the spokes have been a little cracked it weakens the wheel; if the axle shaft has been bent, it is causing undue wear in the bearing; and under all of these conditions there is too much wear of the tires.
During the winter skidding is prevalent, much more so than at other seasons. This is due to the fact that snow and ice keep the pavements wet or icy, according to the temperature. There is another element entering into the situation, however; most folks who travel at this time of the year, because of the cold and discomforts of motoring, desire to get there and so travel faster—the very fact that they are uncomfortable causes them to pay less attention to driving with care. The result is that they run up close behind some other vehicle, which stops quickly; then they jam on the brakes hard and skid. Or, a car comes out of a side street suddenly, making it necessary to swerve quickly to one side, or stop, and the result is a skid in either case.
A rather unusual case of skidding is thus related by a driver:
I was driving up Broadway, in New York City, and to make the hill north of 157th Street had put on a little more speed, for the car was not a good hill climber. A block or two above the subway station a boy on a sled darted out of a side street and swung to continue down the Broadway hill. To avoid hitting him I jammed on the brake hard, and began to skid. There was a wagon at the curb and on the other side of me an auto going in the same direction and there was not room to turn out.
I saw that if my car continued to skid it would swing in front of the sled. It is unusual to skid going up hill, but there was so much loose snow, with ice underneath, that the skid chains did not take hold. There was but an instant to act, much less time than it takes to tell it, and I released the brake and let in the clutch. This stopped the skidding and the car shot forward just in time to let the boy go by.
Probably the greatest cause of skidding is turning the corner at too high speed. This often causes a skidding of the front wheels as well as the rear wheels—that is, the car is going so fast that the front wheels do not get traction enough to change their direction and when they attempt to make the turn they skid and the car goes for the curb. Applying the brake usually will overcome this skid.
In a rear-wheel skid the worst thing one can do is to apply the brake. It is best to let the car coast, turning the front wheels in the direction in which the rear end of the car is skidding; if it is trying to go to the left, turn the front wheels that way. If there is something in the way, so that it is necessary to stop, the brake may be applied a little as the wheels take hold, leaving the clutch engaged, which prevents locking the wheels, as the engine is pulling against the brake and there is not so much danger of locking the wheels. It keeps the wheels revolving slowly, so that you get a better traction for stopping.
It takes a greater pressure applied laterally to start the wheel sliding than to keep it skidding once it is started, and you can bring the car to a standstill much quicker if you can keep the wheels from sliding. A little practice will teach the driver just how much he can apply the brake without causing the wheels to skid.
The bent axle has been mentioned as a result of skidding. It may also be a cause for skidding, for it sometimes happens that by hitting the curb hard, or the wheel of another car, or a street car, the rear axle gets out of true—perhaps the spring-seat bolt will shear off—and the wheels will not track with the front wheels. This will cause skidding.
When there is not snow during the cold months, often water is used to sweep or flush the streets. Wet asphalt is always slippery, whether it is warm or cold, but in cold weather it often freezes and the pavement is dangerous and skidding is almost certain unless care be taken. The street-car tracks are another cause of skidding. Often it is necessary to give the front wheels a considerable turn to get out of the track when necessary, and, especially if they are wet—and they are wet when other parts of the pavement are dry—the rear wheels will continue in the tracks, causing a bad skid. Under no circumstances should one habitually drive in the car tracks when the streets are wet.
If the brakes are adjusted unevenly, so that there is a little more pressure on the one wheel than the other and therefore stops it a little more, it will cause skidding. Another case may come from giving the steering wheel a little twist just as the brake is applied. Occasionally in an emergency stop the driver will give a hasty glance behind to see if a car is close upon him. The hands follow the eye, it is said, and this will often give the slight twist that causes the wheels to slide.
Some cars skid because the weight is not balanced on the wheels—that is, there is too much weight on front or rear wheels. There is a remarkable difference in cars in this respect and it might be well before buying a car to try it out on its likelihood to skid.
There are numerous designs of non-skid tires and they do prevent, or decrease, skidding to a very large degree on some cars. While they help in some cases, it is not well to depend upon them entirely. It is the general practice now to use non-skid chains. On muddy roads they are a necessity and on wet asphalt are almost as essential and chains should be used under such circumstances; but as they cause excessive wear on the tires, they should only be used when needed. The driver should not allow himself to be either too hurried or too lazy to put them on and take them off according to the condition of the pavement. Better to do this a dozen times a day rather than wear out a set of tires or skid into the curb or a street car.
They should be adjusted loosely, so they can creep around and wear the entire circumference of the tire slightly but evenly; if they are so tight they cannot creep, the cross chains will cut away the outer rubber right down to the fabric. A great many tires are ruined in that way. Tires cut this way cannot be turned back to the manufacturer for replacement, for the adjuster will know at once what caused the wear.
Be sure there are a sufficient number of cross chains so that it will not be possible for the brakes to stop the wheel between the cross links, for in that event it will slide just as badly as though no chains were used. As a car is more likely to skid going down grade than on the level, it follows that extra care should be exercised, and that the driver should slow speed for a stop farther away than would ordinarily be necessary, and that the stop should be gradual. One should watch closely on a hill, for there is a greater coasting momentum and a greater tendency for the rear wheels to slew around, because of the weight upon them.
After all, the greatest preventive of skidding is care. The driver who keeps his eyes and wits about him will have his car under control in situations which might possibly cause skidding. It is an essential of economy in tires and wheels and some other parts of the mechanism, and it is an essential in safety, for some very bad, even fatal, accidents have come from skidding at an unfortunate moment, when care would have prevented it. It is no fun to incur injury to person or car, or to pay for repairs or excessive renewals; he who would avoid causes for much of this should beware of skidding.