APPLYING POWER.
APPLYING POWER.
If you wish to remove a bolt that seems to fit too tight and resists ordinary methods, place the nut on the bolt, and screw it on level, so that the end of the bolt will be flush or even with the top of the nut. Then lay your piece of wood, quite smooth and flat, on the nut and bolt, covering both, and hammergently on that with a heavy hammer, with gentle, short, sharp, even strokes. The most obstinate bolt will usually yield to this method of persuasion. Should a burr have formed on the end of a bolt, a file is necessary to remove it; and filing off a burr is a somewhat lengthy and tedious operation.
Unscrew a nut gently and examine it. On the inside will be found a spiral groove and a spiral ridge or thread. Examine the bolt, and observe a similar spiral groove and thread. These, when screwed together, prevent slipping, and the nut cannot be pulled or pushed off. To remove the nut, it is necessary to turn it; and always turn one way, from left to right, if the nut lies uppermost.
To keep a nut from unscrewing by jarring, etc., screw it down until it jams, as it is called, firmly against the surface it rests on. If screwed too tight, it will burst or break the thread, or if enough force is applied the bolt may break. This hardly seems possible until we realize that in the wrench we possess a very powerful lever, capable of destroying quite a large bolt and its accompanying nut. If pains be taken always to start a nut on square and to turn gently and firmly and not too fast, the previous instructions may prove unnecessary.
There are usually two kinds of wrench in a bicycle outfit—an adjustable wrench with sliding jaw, and one or more key-wrenches, so called because made to fit particular parts of the machine, and to be used for them only. The adjustable wrench with sliding jaw should be used with the pressure or pull coming on the angle of the head, and the sliding jaw soplaced as to hold its position, the wrench applied so that the greatest strain is taken at the strongest part; then the faces of the jaw keep smooth and true, and will not deface the plating or polish of the machine.
There is another point to note—that a properly adjusted wrench starts a nut easily, while if the strain is taken on the movable jaw of the wrench, there is give enough in the wrench itself to prevent the nut from starting, and the wrench slips off the nut without effecting its object. The handle of the wrench acts as a lever, and the head of the wrench forms a right angle with the handle; it is here that the power is centred, not at the angle made by the movable jaw. Of course, this position seems the reverse of proper until it is analyzed; but once understood and adopted, it will prove most effective.
There are various screws in and about the machine. A screw is defined as a bolt or bar having a thread cut upon it spirally, so that it will enter a hole in which a corresponding spiral groove and thread have been cut, or on which they will be formed by the screw entering the hole. The thread and screw interwind and prevent the screw from being withdrawn unless it is turned. To turn the screw, a notch is cut on one end, which is made flat for that purpose, and the other end of the screw is pointed, to enable it to enter the hole easily. After a screw is placed and started in its proper hole, it is only necessary to turn it until it is driven home. To turn the screw, a short bar is flattened thin to enter the notch on the end of the screw.
SCREWING UP.
SCREWING UP.
The screw-driver should be held and turned with one hand, and steadied and guided with the other. Metal is not so hard but that the leverage of the screw-driver is enough to bend the notches on the end of a screw, and thus render it useless. The question may be raised, Why are not screws made harder? If metal is tempered too hard, it becomes brittle, and flies. A well-tempered screw should be neither too hard nor too soft, but adapted for its particular use or position.
A screw should always be made clean before it is screwed home, any particle of dust or rust being liable to injure the thread and spoil the screw. If the screw is oily or greasy, it will work loose. All screws, bolts, etc., therefore, should be carefully wiped, and never placed where there is any chance for even a little dust to settle upon them. A nut with a small grain of sand inside will burst or break the thread of the bolt.
Bolts and screws are used to hold different parts together or in place and to give strength and firmness.
There is usually an oil-can belonging to every machine, and a bicycle should be provided with a good one, small, light, and easily carried; and special care should be taken that it does not leak. A greasy oil-can is unpleasant to handle and almost useless, as it cannot be handled properly. The least possible amount of oil that can be used is the proper quantity. Greasy bearings only collect dust, and the dust follows the oil back into the friction surfaces, where its presence is always undesirable.
Two kinds of lubricant are used on a bicycle—oil and graphite. A lubricant is used to diminish friction where two or more surfaces move over each other. If these surfaces are of the same material and the same degree of hardness, they do not slip; but the unevennesses of the surfaces engage each other and cause resistance, which produces friction, and friction causes heat, and the parts move more and more slowly, until at last they stop. Now, if a substance of a different character, like oil or graphite, is introduced between the moving surfaces, it forms little cushions, which prevent the two surfaces from coming into close contact; and, as the oil or graphite splits up readily into minute particles, the surfaces slip upon that, instead of holding fast. A smooth surface of metal is full of inequalities, perceptible when magnified, and slipping past each other with as much difficulty as would surfaces of sand paper. Only oil of the best quality and pure graphite should be used. Nothing sticky or gritty in its nature should be allowed near bearing surfaces.
The pump is an all-important and indispensable adjunct of the pneumatic tire. Each tire is fitted with a valve, and accompanied by a pump with which to inflate it. A valve is a lifting, sliding cover, connected with an aperture to prevent the passage of air or other fluids, and so constructed that the pump forces the cover down, and the air pushes past. The cover is held in place by a spring and air pressure, and, fitting tightly against a washer of some soft, impervious material, makes an air-tight joint, and will not move unless displaced. The pump itselfis fitted with a valve to fill its cylinder or barrel with air, and to hold the air after the cylinder is full and when the plunger of the pump is forcing the air out of it again. A flexible tube coupling is used to connect the pump-barrel with the valve of the tire.
UNSCREWING.
UNSCREWING.
The valves are of many patterns and sizes, and there are pumps made to fit special tires, and pumps that will in a manner suit almost any ordinary valve. It is most important to note that all the washers about the pump and valves are in place. Deflated tires are often caused by a misplaced washer; and though valves are so constructed that it is not easy to disturb the washers, still it is well to know where they are and when they require attention. Washers wear out and require renewing, and sometimes a defective washer should be replaced; they are usually made of rubber or leather, but metal washers are sometimes used where there is much pressure or friction.
The metal used in bicycle construction must be finished, smoothed, and prepared to resist the corroding effects of the atmosphere and to present an attractive and durable exterior. The metal used for the different parts must be smoothed and polished; all foreign substances, like grease, removed from their surface by a chemical process; and lastly a coating of nickel deposited on the surface by means of electricity. The nickel in this way becomes a part of the original metal, and protects its surface from rust and corrosion. A well-nickeled piece of metal, beautifully polished, and kept free from finger marks, loses its lustre only when neglected. Ofcourse, there are other ways of finishing the surface of the metal parts of the bicycle; other plating metal may be substituted for the nickel, and other finish than polish used.
Light wheels cannot be recommended for rough country or for very fast work over only moderately good roads. A certain weight of material has been taken from the bicycle to make it light; the machine begins to lose its rigidity and consequently its accuracy, and cannot maintain its direction, but wavers, and really travels further to attain a given distance. The weight of a bicycle should depend on the roads it is to cover and the purposes it is to serve. Very light wheels wear out quickly; they cannot stand the strain of practice. Beginners, therefore, should choose a wheel that can endure the handling they will give it.
A very light, well-made, and delicately adjusted bicycle can carry a skilled cyclist anywhere; but a light wheel sooner loses its accuracy, and is then more difficult to work than a heavier wheel that runs true. Heavy wheels are not to be endured; light wheels, too light wheels, not to be encouraged.
When choosing a wheel, you should know what you want and why you want it. Machines are built for special purposes, and any reliable dealer can help you in selecting a machine and will guarantee satisfaction. Bicycles wear out, of course, but with proper care they may be made to last a long time.
Careful examination of your wheel should always be made before starting for even a short ride; and on returning it is well to test gear and pedals, to look at spokes and tires. Any needed repair can be noted, and attended to at convenience. Always examine your bicycle thoroughly after a collision, for shocks are dangerous even to the toughest metal, and such precaution may prevent a serious accident.
On returning from a ride the wheel should have a thorough going over, the enamel dusted, and any mud washed off with a wet sponge. The chain, if your machine has one, should be taken off every two or three hundred miles of dusty road, and soaked in kerosene over night; the nickel or metal well dusted, rubbed with a chamois, and polished; and all the bearings, axles, and gear carefully wiped, and dustand grit removed. Then the chain should be replaced, oiled, graphited, and the bearings oiled.
The chain is a complicated mechanism, consisting of many repetitions of parts; it should be kept clean and well lubricated. To apply graphite, turn the wheel upside down, hold the graphite still against the chain, and turn the wheel. The oil is needed in the joints of the chain; the graphite where the chain engages the cogs. The other parts used for applying power need the usual care given to the best machines—absolute cleanliness, freedom from grit, and thorough lubrication.
The chain is at present a mechanical detail only, and the application of power to the wheel capable of a great variety of forms. The principle remains the same, the application of power; the mechanical contrivance for transmitting it is a detail of construction. The difference of individuality can be compensated for in the length of the lever, size and number of gear, size of wheel, diameter of wheel, and width of tread.
The ideal machine requires little adjustment. The less the screws, the nuts, and the bearings are wrenched, the more perfect is the machine, the more free from wear and dents and scratches. To apply a wrench is a serious responsibility that should not be undertaken lightly. It seems easy, and yet skilled men are employed just for that kind of work, for it is work requiring the precision of the trained mechanic.
PREPARING TO TURN THE BICYCLE OVER.
PREPARING TO TURN THE BICYCLE OVER.
After purchasing a watch, the owner does not at once investigate the machinery; yet many, becausethe tools are at hand, are tempted to experiment on a bicycle. A bicycle, like a watch, should be ready to run, and only require winding up to keep it going. It should be adjusted; and if it needs regulating, this should be done by people who understand the machine and have the requisite knowledge and responsibility to do well what is to be done. Two rules may be laid down for one who does not study mechanical details—never to touch the bicycle except to ride it; and never to let any one else touch it who has not skill and experience.
This practice will prove satisfactory until some day, miles from home, the bicycle will not go; you carry it more miles to the nearest conveyance, and send it home. There you have it examined, and find that a touch sets it free; just as sometimes, when your watch will not go, you take it to a watchmaker, and he examines it, winds it up, and hands it back, telling you there is no charge. After learning to wheel a bicycle, therefore, the next step should be to learn to care for it. Unless somewhat familiar with machinery, it is bewildering to contemplate taking the thing apart and putting all those parts together again; even more bewildering is it, having taken the thing apart, not to be able to put it together. In such case, there is nothing to do but to gather the pieces of the puzzle, and send them to be set up. If in this extremity a friend who knows all about a bicycle should offer assistance, it is well to hear what he has to say before he undertakes the work. “I do not think your wheel is just like mine,” perhaps, or “Where do these things belong?” is enough for the wise. Better send to the shop for a machinist at once. All the parts of the bicycle are made to go together in one way, and any attempt at experiment may injure the mechanism.
When you undertake to investigate a bicycle for the first time, take an old one as a subject, and endeavor to put it in perfect running order. If an old bicycle cannot be had, proceed with much circumspection. Go where you will be undisturbed, where there is plenty of room, and where a key may be turned if there is possibility of interruption. There is sure to be some oil and grease spattered about, in spite of the utmost care, and it is well to remember this while making preparations. Have ready a pile of old newspapers, some cups, plates, and boxes, and a painting apron if you possess one; if not an old skirt and apron, and sleeves well rolled up. For tools, a monkey-wrench, two or three screw-drivers, large as well as small, a hammer, one or two pieces of wood, the bicycle kit, oil, graphite, a can of kerosene, some cheesecloth and canton flannel, and a large wooden box.
Take two newspapers folded in half, and put them on the floor for the saddle and handle-bars; then turn the bicycle upside down, and arrange the newspapers under the saddle and handles. If there is a bell, take it off, or place a block under the opposite end of the bar to balance it. Before turning the bicycle over, remove the lantern, if there is one on the bicycle, as the oil will be spilled out if the lamp is turned upside down.
TURNING THE BICYCLE OVER.
TURNING THE BICYCLE OVER.
Begin by carefully removing all mud and gritfrom the bicycle. Wear old gloves, and remove mud with the hand when possible, finishing with a cheese-cloth duster and an old oily cloth. Go over all the joints where the wheels turn, and remove every particle of grit, then remove mud and dust.
An experienced worker, to save labor, cleans each piece as it comes off, but the beginner must work more slowly. Have ready a shallow box or tray to receive the parts as they are removed. Lay each part, as it is taken off, in the tray, with the oily side up, for a guide. First, remove the chain, turn it until the nut of the little screw-bolt is found. This little bolt forms one of the link-pins, and can be found quite readily. One end of the bolt has a screw-head notch, and the other a nut and thread. Use the small bicycle screw-wrench for this, a large screw-driver, and a small screw-driver to fit the screw. Turn the chain until the bolt is in a convenient position, then take the large screw-driver or a rod, and place through the spokes of the rear wheel, letting the bar rest on the frame. This will prevent the wheel from turning, and keep the pedals and sprocket-wheel in position; your fingers may be caught and badly cut if this precaution is not taken. Fasten the small wrench on the little nut, and hold it there with one hand, with the other unscrewing the little screw with a small screw-driver. Should the screw fail to yield easily, a drop or two of kerosene will soften the rust and grit, and help to start it.
Return the nut to the screw end, and place it on the tray. Take hold of one end of the chain, and remove the bar that steadies the rear wheel, thenturn one of the pedal cranks, and the chain will come off in your hand. The chain should be placed in kerosene and left to soak.
The enamel of the frame should then be carefully rubbed and polished with canton flannel. A clean piece should be kept for the purpose, for if greasy it gives a dull look to the enamel. The plating should be first polished with a cloth, and then if dull with whiting. Nickel plating takes a beautiful polish with electro-silicon used on canton flannel.
Go carefully over each oil-cup, and be sure it is cleaned, and work around the ends of the axles. Ascertain if either wheel needs adjusting, and look carefully to see that the rims are true. A good way to do this is to hold a pencil-top on the frame against the rim of the wheel, and spin the wheel. If it touches evenly all around, the wheel is true; if uneven, take the bicycle to a repair shop and have the wheels trued as soon as possible.
After cleaning all the bearings, put oil in the oil-cups and replace the chain. It is well to leave the chain soaking in kerosene, and later hang it up to drip, and when dry, it will be found bright and clean; or keep a can of lubricating oil in which to soak the chain, and after draining it thoroughly, wipe clean before replacing on the machine. Take an oil-can, and oil each separate rivet. Start the chain on the sprocket, and pull it over the rear sprocket by turning a pedal crank, bringing the ends on the lower side. Place the bar across as before, to keep the sprocket from moving, and then replace the little screw-bolt, using a small wrench, and a screw-driverthat fits the screw. Remove the bar, see that the chain is not too tight, and note if it requires any taking up, an adjustment that is done in the rear wheel.
THE BICYCLE TURNED OVER.
THE BICYCLE TURNED OVER.
Hold the stick of graphite on a convenient surface of the chain, and turn the cranks; then dust the chain to take off any small lumps of the lubricant, and the wheel is ready to be run. Examine the tires and valves, see that the tires are not too soft, and inflate them. See that the valves are in order, then set the wheel right side up. Replace bell and lantern, rub off any finger-marks, and the bicycle is ready.
If the bicycle has been running for some time, and in spite of the care bestowed on it, the chain runs a little heavy, the pedals don’t spin as they should, or the cranks revolve as often as they might, and the wheels are sluggish, there is no remedy but to take down the bicycle, clean it thoroughly, set it up and adjust it. It will require several hours’ hard work to do this, combined with a knowledge of machinery and a knowledge of bicycle working, or else enterprise, care, and common sense.
Begin work on a wheel perfectly free, as far as the outside can be made so, from sand, mud, and grit. Remove the chain and put it to soak. Have a pan of kerosene, and place each small part in that to soak, and any part that has friction surface or is notably oily or greasy.
Begin serious work on a pedal, which is small and easily handled. If the pedal is a removable one, take it off. If the spindle is stationary, take off themovable parts, first the nuts or screws, then loosen the cones, having a box placed underneath to catch the balls if any should fall out. Support the box well up under the pedal, as the balls bounce and jump about. Even if you have had the pedals off before, and know how it is done, it is well to have something to catch the balls, as otherwise you must atone for any mistake by a scramble. Place the balls in a separate dish of kerosene, and carefully count them. Wipe the movable parts of the pedals with a cloth wet in kerosene, and finish with a dry cloth.
In taking a pedal down, the place of each part should be carefully noted, so that it may be a simple matter to replace the parts. If, the first pedal being now apart, the novice is confused, there is the other pedal to afford comparison. Study that, then return the parts of the dismembered pedal to their proper places, and adjust them. The balls may prove troublesome; but a screw-driver dipped in vaseline will pick up any very small balls, and pliers can manage the larger ones. See that cones and washers are replaced, then add a few drops of oil, adjusting the pedal to spin easily without lateral play, and tighten cones and nuts. Spin the pedal for a final test, and then begin on the other pedal.
If after several hours’ work, but one pedal is finished, if that one pedal is in perfect order, there is much cause for congratulation. The other pedal may be done very much more easily and rapidly. Of course, it takes time to wipe all the balls and cones, and nuts and screws, and washers and spindles, and when the pedal is in your hand, a littletime may be spent to give it an extra rub to brighten its polish. Wipe off any oil that may have shown in the joints of the bearings, and the pedals are finished.
The front wheel should next engage attention. Take a large wrench, and start the bearing cones, and take off the nuts at opposite sides of the ends of the forks. These nuts are screwed on the ends of the axle, and perhaps have metal washers under them. Place them in a box by themselves, and if the forks are notched, there will be nothing to do but to lift out the wheel. If the ends of the forks have only eyes, the forks must be sprung to take the wheel out.
When the wheel is in your hand, avoid letting any grease or oil touch the tire, for it will injure the rubber. Now proceed to work on the axles. Support the wheel on a large, empty wooden box. The axle is a spindle, and has cones to hold the balls in against the bearings. The cones must be removed and cleaned, and the socket of the hub made clean with an oily cloth followed by a clean one. The axle’s spindle should be replaced, and the balls and cones restored to their proper relative positions. Drop in a little oil, adjust and tighten the cones, then spring the wheel back between the forks, and true it; see that it runs even between the forks and that the cones are keyed up firm and even. Replace the nuts, and screw up firm. Wipe off any oil that may have worked out, and spin the wheel to try it. If it runs long and steadily, and has no lateral play, and everything is keyed up tight and true, this part of the work may be considered finished.
Some prefer to use a little pure graphite for the balls, and no oil; and again some bicycles are made without oil-cups. For the first work, oil is safer to handle; but remember that two or three drops are enough. Too much is worse than useless, for oil spreads over a large surface, and will cover all the surface of the bicycle with a thin film, which will need to be constantly wiped off.
The rear wheel may be removed without springing the frame. Unscrew the adjustment attachment, and the wheel will come out. Clean the rear wheel bearings in the same way you have cleaned those of the front wheel; replace the rear wheel, and put back the adjusting attachment.
Give the crank axle the same care and attention that the wheel axles have received. The pedal cranks are fastened on either end of the crank axle in such a way that the dead centre is avoided as much as possible. The large sprocket-wheel is on the crank axles, and sometimes not movable. The cranks are screwed or fastened with pins to the ends of the axles, and should not be disturbed. Take the large key-wrench from the kit, and start the bearing cones. If the crank must come off, see that the nut on the end of the crank-pin is flush with the end, and place a piece of wood on it before striking it with a hammer, as already explained, to start the bolt or pin. Or if you have some one to help, let a heavy hammer-head be held under the crank beside the bolt, at the other end; and the double shock and recoil from the heavy hammer as the blow is struck will jar the bolt loose.
Remove and clean the cones and balls, then replace and oil them, and adjust the cones tight, ready for adjustment when the cranks are in place. The only bearings left to attend to are those in the head of the frame. Take out the handle-bars, and wipe them and their socket very carefully; never allow any oil to remain there. The handles should never be immovably tight; yet grease, if any were introduced, would perhaps cause them to slip when they should remain in place. The crank axle-key usually fits the cone of the head of the frame, and that may be treated as any other set of ball bearings—loosened, removed, cleaned, replaced, oiled, adjusted, and tightened. Any dust may be removed from inside the frame-head while the bearings are off.
When the head bearings have been restored and the handle-bar replaced, put on the chain and adjust it. The rear wheel is arranged to move forward or back on the frame by the adjusting attachment. This allows the two sprocket-wheels to be placed nearer together or farther apart, and the chain may be stretched and held between them to any desired degree of rigidity or of slackness.
When the bicycle has been set up, the parts correctly replaced, before turning it right side up, go over the entire adjustment of the machine, to see that nothing has been forgotten. Have wrench and screw-driver at hand and a clean cloth. Begin with the bearings of the front wheel. See that the oil is not working out, and wipe them again. Take the key, and see that they are true and tight. Apply the screw-wrench to the nuts of the fork, and see thatthey are screwed home. Treat the rear wheel in the same way, and look that both wheels travel on the same line or plane; if they do not, it is because the bearings are out or the frame is bent. Go over the axle bearing, feel the chain, spin the pedals and wheels. A well-adjusted wheel will carry the weight of the valve around quickly and then swing back, showing how sensitive it is to so small a weight. If you are satisfied that everything is right, turn the bicycle right side up, and square the handle-bars. The only way to do this is to stand in front of the bicycle, and take the wheel between the knees while the handles are pulled into place.
The saddle-post and screw-nuts that hold it should be examined and removed and carefully wiped, as well as the socket where they belong. The screw that holds the saddle-post in place does its work by friction, and any oil would prevent it from acting properly, and the saddle would slip. Keep the oil-can carefully wiped, and see that the little spout has a clean round hole at the end that will allow only a drop at a time to escape; for oil travels and spreads in a marvellous manner, appearing where least expected or wanted. If there is a hand-brake on the bicycle, adjusted to alter with the handle-bars, examine it carefully, and wipe the rods. Oil here will allow the coupling to slip and the action of the brake to be impaired.
STRAIGHTENING THE HANDLE-BARS.
STRAIGHTENING THE HANDLE-BARS.
There are so many things to be carefully observed and accurately done in this kind of work that mistakes and omissions may be easily made by the inexperienced; but there need not be so many blunders,after all, if one works slowly and observingly, taking notes, in writing if necessary, as for instance how far the bearing cones are keyed in when in place, which is the reverse side of the crank and pedal pins, if they are interchangeable, or rights and lefts.
Screw threads are made rights and lefts, and threads are made to fit them in the sockets where they belong. That pedals may not work loose, the spindles are made right and left, with a reverse screw, so that forward pedaling drives them tighter. In the older constructions, the pedal sometimes became unscrewed and fell off, or the nut fell off and the pedal loosened. All such matters should be studied before taking down a machine. Usually the maker’s catalogue will describe and illustrate these details. Study that, and learn the names and uses of all the parts of the bicycle, and then you will be prepared to go to work by yourself, or with but little assistance.
Almost anywhere that a bicycle can stand or hang will do for a place to keep it; and almost any place will do to go to work on a bicycle—the roadside, the lawn (though the grass is worse than a haystack to lose things in), anywhere, in fact, that may suit your convenience. The accessories of the bicycle should have places where they may always be found, and the bicycle itself should be kept where it will be undisturbed and where it may be kept free from finger-marks, dust, and oil.
With the bicycle should be kept certain conveniences for handling it—a table or bench fitted conveniently, frames to hold the wheel for cleaning and adjusting, a good light to work by, and a place for the tools that are sure to accumulate. There are two kinds of workshop for the amateur—the one that you fit up for yourself, and the one that is fitted up for you. The amateur with a place well fitted out likes to add details of home construction, and the proud owner of a corner cupboard is always anxious to replace makeshifts. In either case, get the best you can, and take care of it. Of tools, the best are always cheapest; but good tools, or tools of anykind, can become a very expensive luxury. Taste for the best comes quickly to even the moderately enthusiastic.
A bicycle rack room should be light, with plenty of head room, and conveniently fitted with racks, shelves, and lockers. Each rack should have its corresponding shelf-room and pigeon-hole, either beside it or above and behind it. There is an infinite variety of racks to select from, from the two stakes driven into the ground or fastened to the floor, to the handsomely finished metal racks with joints to hold the frame at any angle.
If there is but one bicycle to care for, it is better to have its rack and shelf and cupboard together—the rack to hold the bicycle in a proper position, the shelf for sundry attachments, and the cupboard for the lamp and extras. Such a bicycle corner can be made very attractive to look at when everything is arranged and kept in perfect order. When several bicycles are to be cared for together, when neatly set up they make a very pretty showing. If possible, the rack-room should be separate, set apart for that purpose, and kept under lock and key; it should be dry and well lighted, free from frost, and not likely to be over-heated by direct sun-rays in summer. The frost is injurious to metal and enamel; and the sun or too much heat will spoil rubber, and possibly injure enamel as well.
An even temperature, not any special degree of temperature, is requisite; for changes of temperature cause different degrees of expansion and contraction in different materials; and as the steel frame, andthe enamel it is covered with, do not expand and contract in quite the same degree, they will gradually work loose from each other, and the enamel will flake or split.
The rubber tire should be kept out of the sun, and the place where it stands should be kept very clean, and no oil allowed about; for oil is injurious to the rubber, and in case of punctures makes repairing very difficult, if not impossible. A rubber surface with even the slightest film of oil will not make a joint, as the oil prevents the rubber surface and that of the cement and the article to be repaired from uniting.
If the workshop is to be used by more than one person, each should have a tool-chest and a work-bench of his own, and each tool-chest provided with lock and key, and each person with a key to the outer door. Tools are but the continuation of the individual brain and will power. What one handles becomes, while in one’s hand, a part of one’s self, as it were. Tools, therefore, should be individual property always, just as scissors and thimble are, though of course extra tools may be provided for general work. Every one prefers a good pair of scissors to a poor pair, and the same preference is likely to be evinced in the case of other tools. If the tools are common property, the best will be always taken, and often not restored to their proper place.
A bicycle workshop is devoted to metal work, woodwork, and rubber work. The metal work should be kept by itself, and the tools used for metal work only.
The amateur can commence fitting a shop by setting up a small deal table and a vise. The table will do for a work-bench, and one vise will serve for a beginning; it should be of medium size, quite heavy, made of wrought iron or cast steel, and capable of holding a wrench in its jaws, though a less expensive one could be made to do. A cheap vise, however, is pretty sure to break if a strain is put upon it; and, while a good workman could get comparatively good work out of a poor vise, the poor tool in unskilled hands would be sure to show its weak place.
Have a notch cut in the edge of the table to let the vise back to where there is bearing surface; and it is well to have it as far in as convenient, for the weight will thus be supported more steadily. Get a plumber to cut a section of lead pipe about as long as the jaws of the vise, and have the piece of pipe split and flattened. You can do this yourself if you can handle a saw, and have one that is suitable for cutting metal; or a jig saw will do, and the lead can be flattened on a block with a mallet. Screw one of the flattened pieces of lead into the jaws of the vise, leaving about an inch to project above; hammer the projecting part over, and one side of the jaws will have a lead face that can be taken out. Do the same with the other piece of lead. Replace them both, and the vise is fitted with a pair of lead jaw faces, which will be found most useful.
The lead being soft, any small metal object may be held between the jaws without injury, while if the steel face of the vise came in direct contact with the metal, a screw for example, the thread might bebruised; or if the screw were harder than the vise, the face of the jaws would be marred.
With a work-table, a vise, and the bicycle kit, a very fair beginning may be made, and any refractory small part handled with ease. Even the spindle of the axles of one of the wheels may be screwed in, and the bearings removed, while held in this way. The vise will act as a clamp for holding pieces to be polished, and it is most useful in taking a pedal or other small parts down. Above the table should be a tool-rack, three feet of board ten or twelve inches wide, with a ledge or shelf nailed along the lower edge, and a strip of leather or some stiff and pliable material nailed on in loops to hold the tools. Under the table should be kept a couple of boxes—wooden boxes such as canned goods come in will do—one as a receptacle for oil-cans, kerosene, and cloths, and the other to use as a frame. The outfit should be completed by a little bench, and a wooden stool to sit on when working at the table; for much of the work about a bicycle may be done while seated comfortably, and it is always well to save strength when possible.
A workshop once started, many little contrivances suggest themselves for convenient working,—a nail must be put up for the apron, a corner found for the working gloves, separate places allotted for oily cloths and clean ones and for the kerosene. The bicycle lamp, if an oil-lamp, should have a stand for trimming and filling, and should be cared for regularly; the best of lamps will smoke occasionally, and the soot must not be allowed to fly about.
From fitting up a bicycle workshop, the transition is easy to studying accomplishments that may be of use—planning tours and trips, exercising scientifically to prepare to enjoy them, studying the construction and improvement of modern contrivances, learning the use of map and compass, investigating camping possibilities, and learning how to depend on limited resources when cut off from supplies. The simple appliances and contrivances of the home workshop lead the mind to appreciation and desire for something better, more workmanlike. A choice of tools suggests itself; and from the first assortment of a couple of wrenches, a few screw-drivers, a hammer, and a couple of wooden boxes, is finally evolved the well-furnished amateur workshop.
The ideal room for this purpose should have a good north light, with windows on two sides if possible, and high enough from the floor to allow a work-bench to be placed in front of the window with the light falling upon it, and a space of ten inches or a foot between the lowest part of the window and the bench; this space to be arranged as a rack for tools. The windows should open and shut easily, and be fitted with two kinds of shades, dark green and white, two pairs of shades to each window, two rolling up from the lower part, and two down from the upper part. Nothing is so fatiguing as working by light not suited to the work to be done. With shades arranged in this way, light may be perfectly controlled, and distributed where needed by means of reflectors. Ventilating and heating, also, must be arranged for.
The workshop should have running water, and a closet for working clothes, which are apt to be oily or greasy. There should be plenty of shelf-room, and an extra cupboard or two. The floor should be of wood, unpainted. There should be a bench for carpenter work and carpenter tools; a bench for cabinet-working tools for fine wood-working; a table for rubber and naphtha; and a long, heavy, narrow bench fitted with vises of different sizes and patterns; a table devoted to the blast furnace, a corner for an anvil and portable forge and another for a lathe and power-saw, though these may be dispensed with. The movable furniture may consist of stools and benches of different heights, and the frames necessary to take down and handle a bicycle on.
Metal can be bent, twisted, cut, pressed, elongated, sawed, stretched, and melted into any shape desired. The tools adapted to this work may consist of holding tools, carving tools, molding tools, and bending tools; and contrivances and tools made to perform certain work, as screw-driver, etc.
Cutting tools are knives, saws, files, and chisels, which perform their work by applied power, whether controlled directly by the hand or otherwise.
The metal-working outfit may contain many varieties of tools.
In the older forms of wheel, the tire did duty in protecting and strengthening the wheel and holding it together. In the bicycle wheel, the rim is the strengthening and supporting contrivance. The tire protects the rim, and acts as a spring cushion as well, receiving shock and jar. The solid rubber tire was an advance over the old steel tire on the bone-shaking machine, as it was called, in the days when the bicycle was still in its experimental stage.
The solid tire was narrow, and after a certain diameter of material was reached, the weight of rubber became too great if the tire was made larger. It was found that a certain thickness of material was sufficient for wear and tear and that more surface was desired to grip the roadway, and that consequently the tire should be made lighter. Hose-pipe was tried, and did well; and then experiment succeeded experiment in the effort to produce a tire that would fit, wear well, be light, and give speed and resiliance.
A pneumatic tire is made of a tough, hard outer material to resist wear, a fibrous inner material to give stiffness and prevent stretching, and an imperviousinner layer to retain the air. Rubber is a sticky, gummy substance, easily melted at a comparatively low temperature, and becoming hard when exposed to the air and moderately low temperature; it dissolves readily in benzine or gasoline or naphtha, and is insoluble in water. Grease and oil have a peculiar disintegrating effect on rubber and rubber materials, and are most injurious to them. To prevent rubber substances from adhering to each other, they are prepared in a particular way, and feel dry and gritty to the touch.
Tires are made in layers, and double-tube tires have a separate inner tube of impervious rubber to hold the air, and an outer covering of toughened material, that is quite separate and not necessarily air-tight, to resist wear.
The tire must be held immovable on the rim of the wheel. There is all the pull of the weight of the moving bicycle against the surface over which it moves, and the tire must be secured to the rim in such a way as to keep it forced in place. There are two methods of fastening it permanently to the rim,—with cement or other material of that character, so as to make it a part of the rim, as it were; and by clamping it fast. A cemented tire, or indeed any tire of rubber, should never be left in the sun, as the heat affects the rubber and perhaps the cement.
Changes of temperature affect different materials in different degrees, and the different materials expand and contract, working loose from each other until something gives way, with apparently inexplicable results. When two or more different materialsare used in construction in this way, this problem will always present itself.
The tire inflated, the impervious inner covering of the tire tube, which is made of a soft and yielding substance, fills the interstices in the outer covering, rendering it air-tight. Should a hard substance then be introduced into this material, and a puncture occur, it is necessary to locate the puncture. This is very difficult to do if the puncture is small, and the substance that made the hole has been removed. Ascertain first that the trouble is not with the valve of the tire if the air is not retained properly. Then test for puncture in this way. Wet the surface of the tire, and note the bubbles that form under the film of water, and the puncture is found.
The inner surface tire is made to resist the air, and is usually of pure rubber. The outer covering is for strength and wear. Rubber may be repaired with rubber easily enough, and the purer the rubber, the easier it is to cement it with a cement made of pure rubber dissolved in a volatile vehicle. Almost any repair or renovation of the tire may be accomplished with rubber material, rubber cement to be used for plugging, and twine or cotton cloth to be used for strengthening purposes. Small punctures require only plugging from the inside; tears and rents require plugging and reinforcing as well. Each make of tire has its repair-kit and directions for use.
The single-tube tire, with its inner coat, is so made that the inner covering will act as a continuous plug. The soft rubber is compressed, and put on in such a way that the air pressure, even if a puncture occurs,will help to close the hole by pressing on all sides around and about it. To illustrate this principle, cover the outside of the tube with soft rubber cement, and let it dry. Then turn the tube inside out. The rubber will be in an active state of compression. Force air against the surface, and it is easily seen how the rubber is crowded if there is any place made by puncture, and how the hole would be closed.
Numberless punctures are made and resealed, and the tire works all right. The puncture that does not reseal must be plugged or patched. Rubber plugs are made in all sizes; and rubber cement, liquid rubber, is put up in collapsible metal tubes, like paint-tubes, with a pointed spout to introduce the cement behind and through the puncture. There are numberless convenient contrivances made to hold plugs, enlarge holes, and to do the repair work neatly.
In mending a puncture, the tire remains on the wheel, and the work is done from the outside of the tire. If the hole is very small, it must be enlarged sufficiently to introduce the plug. The rubber of the plug is very soft and compressible, and the hole should be considerably smaller than the shank of the plug.
The plug must be held firmly, and forced through the hole, and held in place while the nose of the cement-tube is introduced, and a plentiful supply of liquid rubber smeared over the inside of the hole around and on the plug, and enough extra cement added to flow all about the inside of the tire around the puncture. Pull the plug back by the shank,allowing the head to rest on the inside of the tire, and the shank to come back through the hole. Pull the plug firmly into place by the shank, which should fit the hole very tight. Cut off the projecting end of the plug shank, and the repair is made. Turn the wheel until the plug comes to the lowest point, and keep it there until the cement gets around the plug. To smooth a ragged hole before introducing the plug, when the proper tools are not to be had, a heated wire may be used to make a round smooth hole. Rubber may be handled and cut while wet with water, but must be dry and free from grease to take cement. Always wet the knife-blade before cutting the end off the plug; this will ensure a smooth, clean cut.
A puncture may be repaired by introducing almost any material on the inner surface, and holding it in place; and it is well to know of a few substitutes for the regular repair-kit for emergency use. Punctures difficult to locate may be found by inflating the tire and wetting with soapy water, when a bubble will form where the air escapes.
A puncture that goes all the way through the inner tube of the tire must be repaired on the inside. The outer covering of the tire is porous, and if the hole is plugged or patched on the outside, the air will escape in other directions through the material of the tire. Failing the repair-kit tools, a rubber plug, some liquid cement, a piece of string, and a pair of pliers will do good work. Tie the string to the plug to keep it from slipping, apply plenty of cement to the plug, then grasp it with the pliers, and introduceit through the hole prepared for it in the tire. Pull the string to pull the plug into place, see that there is plenty of cement around and about it, inflate the tire, and the air will hold the plug in place until the cement hardens.
The plugs that are supplied are disks of rubber of different sizes, with stems attached to the centre, and a nice tool is made for the purpose of punching the hole in the tire. When a hole is burned, the charred edges should be removed, and if possible cleaned with benzine. A tire well patched on the inside is almost as good as new, and very serviceable, unless the brake is applied frequently and unevenly, when the plug is almost sure to feel the push.
The commercial patch or plug makes the most satisfactory repair for a puncture, although there are other things that may be used. Rubber bands may be pressed into service, and sheet rubber also may be used. Repair on the roadside is made in the same way as repair in the workshop, the differences being in the conveniences for working and the permanency of the patch. A rent may be repaired with plugs, it being first stitched together, then the plugs introduced, and finally a patch cemented on the outside over the rent to protect the stitches. A puncture may be repaired with rubber bands held in place on a wire, covered with cement, and forced into the hole made in the tire. A piece of wire flattened on the end, a cross piece with a notch cut in it and twisted below, makes a fair repair needle. The end of the projecting rubber cut off, a very fair plug results.
Sheet rubber may be placed over the hole on the inside, though it is difficult to keep it in place. Twisted up and tied into a plug, or spread into place on the inside, the difficulty with this repair is that the patch must be held in place until the cement hardens, and then is liable to work out of place. Inner tube tires are repaired with patches of soft rubber. After the puncture is located, the patch will retain its place by being pressed against the inner surface of the tire when inflated.
To do good work in repairing rubber, always clean the surface of the rubber material thoroughly, washing with benzine when possible; and always test a patch when finished by placing it in water or wetting it, to ascertain that it is satisfactory. On the road a puncture may be plugged in any time under five minutes when located. In the workshop, it is more convenient to hang the wheel up while making a patch, as it is more readily held in place when working from below.
There are many ways of doing makeshift repairs. Melted rosin may replace the rubber cement, and rosin may be found at any tinsmith’s. Melt the rosin, and dip the rubber in that to make it stick.
Tire tape may be used in a variety of ways. Find the puncture, cut strips three or four inches long, and place them lengthwise on the tire, lapping the edges at least half way over; then wrap the two thicknesses of tape round and round the tire, and keep lapping the tape each time over the last turn to hold the edge down, making it air-tight. Well put on, tire tape will last for many miles. The tire shouldbe partly inflated while the tape is being put on, and fully inflated when it is all on. Force more air into the tire to cause the tape to grip securely. Such repair, though not permanent, may prove serviceable in emergency.
A simple and effective substitute for the rubber plug is absorbent cotton or jeweller’s cotton, well dipped in cement, and the cement worked into the cotton. Quite a large puncture may be repaired with this, and the hole need not be enlarged or burnt to receive it, as the soft mass of cotton fills the irregularities in the puncture. It may be introduced into the puncture either with an ordinary repair tool or a piece of twisted wire. The tire is held on the rim by cement made of shellac or some other equally good cementing substance. Of course, in using a cotton plug, the greatest mass of the cotton should be on the inside of the tire, leaving a stem in the puncture, and then the outside ends should be trimmed off.
The tire may be readily removed with the hands by pulling at right angles with the wheel. Rubber cement may be made by dissolving perfectly pure rubber in naphtha; but the commercial cement is usually found the cheapest in the end.
If you should be so unfortunate as to break down, what are the problems you must meet? The bicycle is made of different materials—iron, metal, steel, wood, rubber, and leather, and each different material requires a different kind of treatment. The general idea in any kind of repairs is to effect the holding of the parts in position with a material that willsupply strength and stiffness. The use of glue or cement is merely to hold parts in position, to replace the fractured pieces and keep them in place, to enable the particular part to do its duty, and to keep the piece in place while the cement hardens.
There is room for great ingenuity in handling repair work and in estimating the available resources. The most common accident is a puncture in a pneumatic tire. There are also repairs to be considered to the wooden rims and the spokes and the tubing and lost or broken parts. A great deal of damage could occur in a collision, and the bicycle be in very poor shape, but it can be set right with a little assistance from a mechanic, even though he does not understand the mechanism of a bicycle.
Suppose nothing to be injured except a piece of the supporting tubing; or that the bicycle could be made to go if the rim were spliced or strengthened at a place where it has been split. A temporary repair usually takes considerable time, and should never be attempted unless there is nothing else to be done. A blacksmith shop, unless the smith is very ingenious, is not a very good place to look for assistance; a plumber or tinsmith or locksmith, unless a bicyclist, can help but little. For a broken rim I would betake me to a carpenter shop or carriage maker’s. If the break is in a straight piece of tube, get the carpenter to make a round stick, not as long as the broken tube, and fit it to the inside, to slip in easily. Hardware stores keep round wooden rods, and perhaps one of these would answer. Push the round stick up into the tube, and,holding the parts in place, let it slip down into the other part of the break; this will keep the ends of the break together. Then get the carpenter to take two blocks of wood, hollow them out to hold the tube, and screw them fast together, holding the tube between them. If he has an auger-bit the size of the tubing, he can easily bore a hole in a block the size of the tube; then have this block cut in two with the saw, leaving the hole cut in half, and screw the pieces together after they are placed on the broken part. The same kind of a repair may be made on the angles of the frame if the blocks are hollowed to fit. This makes an unsightly job, but can be recommended as strong and safe when properly done.
A broken spoke may be repaired, if it cannot be replaced, by bending the ends of the broken parts into loops; then, taking a piece of wire through both loops, fasten it together, and tighten by screwing it up.
A wooden rim may be whipped or wound. The tire must be deflated first, and removed from the rim at the broken place; then wind fine wire or fish-line about the place, after filling the break with glue or shellac. In wrapping, take care that the turns are made very smooth and even, and close to each other. Then the tire may be cemented and inflated. Of course, there will be a lumpy place on the rim, but it will do until the rim can be replaced.
Any bolt that has lost its nut, when the nut cannot be replaced, may be held by hammering a burr on the end. If the end is too long, a piece may be cut or filed off, and a burr hammered down to hold.
A bicycle cannot travel easily if the frame has been bent out of true; and to straighten a bent frame is an easy matter. Take out wheels, saddle, and handle-bars, and use a piece of broom-handle to spring the frame into true; or take a stout cord, fasten it to either end of the part to be straightened, insert a stick, and wind the cord up tight.
There are three things to take into consideration when doing repair work: First, finding out what is to be done, then doing it, then seeing that it has been done right.
All applied mechanical power is the application of lever movement (and lever movement is but the effect of applied power), either simple, compound, or complex.
In the bicycle propelled by human power, we have a series of lever movements, initiated and executed by the highest and most effective mechanism known—the human body, applied human power. There is the seat of power, the point of application, and the object. The bicycle or object is so constructed that it continues the application of power applied.
The lever is described as “a bar or other rigid instrument having a fixed point for the exercise of power and the application of power to the object to be moved.” The series of lever movements in the human body is the most wonderful known.
There are three varieties of levers, of three different degrees of efficiency, known as levers of the first, second, and third classes, or orders, of levers.
In the lever of the first class, the fulcrum is between the weight and the power:PFW.
In the lever of the second class the fulcrum is opposite to the power:PWF.
In the lever of the third class the fulcrum is opposite to the weight:PWF.
These different powers of levers are used in combination, and produce a great variety of power effects and applications.
Other factors to note are:
That a body in motion persists in maintaining its direction unless other forces intervene.
That the gyroscope overcomes the force of gravity while rapidly revolving.
That a body set in motion tends to move in a straight line.
That the centre of gravity must be maintained by balance if disturbed or shifted.
That force is the cause of a change in the velocity or direction of motion of a body.
That all alterations of velocity take place gradually and continuously.
That centripetal force and centrifugal force are force directed by radial action.
That the air offers resistance, which increases when the air is in motion.
That friction offers resistance to power.
That the smaller the surface presented, the less friction there is to resist.
That resistance must be overcome by power expended for the purpose.
That the base of the bicycle is practically withoutwidth, and is usually about from forty-two to forty-four inches long.
That the direction of the base may be changed at will within certain limits.
That the bicycle will fall unless prevented from doing so.
That to prevent a bicycle from falling, or to maintain a bicycle on its base, it is necessary to balance it.
That the constant effort to maintain the bicycle upright upon its base is on account of the motion of the different opposing forces.
The bicycle is constructed to overcome the resisting forces in different ways, supplying as many forces as can be made available to accomplish a particular purpose, permitting a certain choice and discrimination in the matter.
The bicycle has one weight-carrying wheel and a frame and a pivoted wheel. The driving power is applied to the weight-carrying wheel, and the steering is done with the pivoted wheel. The bicycle remains upright because several forces co-operate to enable it to maintain its plane, change direction, and overcome certain resisting and opposing forces.
A bicyclist is propelled at a sufficient velocity to maintain the plane of movement. By altering the centre of gravity, inclining one way or the other, change of direction may be made.
The front or guiding wheel of the bicycle, being controlled by the different angles of resistance it presents to the surface it rotates upon, and not being immovably fixed, can pivot to a plane corresponding to a plane of least resistance. After a little momentumis attained, a bicycle will maintain its speed with but little assistance of power, unless it is accidentally obstructed, or an increase of grade requires an increase of power.
The frame of a bicycle is a compound lever, combining the second and third orders. The wheels are a compound lever of the second and third orders. The fork and handles a lever of the second order.
The forks and handle-bars are set at an angle with the front wheel, thus conveying the touch on the ground or other surface to the pivot head and the hands.
A moving body tends to pursue its direction. A wheel loses its power to change its direction after passing the point of friction. With the forks at this angle, the blow is felt, and change of direction caused by an obstacle conveyed; but the wheel has still some power to maintain its plane from friction, and is steadied by its head. The motion of swaying is conveyed and overcome at the tire base. If the pivot were directly over the tire base, the swing would be given to the wheel; and the tire, having passed its point of friction, would continue to swing. If the head were pivoted on a point, there would be no side friction on the rim; because it is pivoted at an incline, the friction base is increased in proportion, and the wheel, steadied in itself, is easily controlled by an increased line of friction or by prolonging the time from the point of contact.
A body in motion persists in maintaining its plane of motion unless additional forces intervene. The occurrence of these forces is detrimental and frequent,requiring a continuous swing of the guiding wheel either by the hands or by balance. The direction of the base line is continually changed, as it were, broadening the base line. The weight must incline with the front wheel, and the front wheel will support it. If inclined away from the direction of the front wheel, the weight becomes the long arm of the lever, exerting weight against weight at the base of the bicycle, there being no opposing force. The front wheel being turned away, the bicycle falls or slips over.
With the fork at this angle the wheel is inclined, the frame held on the wheel at this angle, as the wheel is turned sideways, it gradually brings the centre directly over the axles, raising the front end of the frame up. This pressure or leverage from the frame tends to keep the wheel straight in the line of least resistance. In turning, the wheel must lift the weight, and push it up; and this factor greatly adds to the steadiness of direction.
A bicycle with the steering wheel held fast will maintain its plane so long as its momentum is not overcome. With the steering wheel the plane of movement may be regained after each opposition, provided the proportionate amount of power is expended.
The radius of a wheel is the long arm of a lever; the pedal crank is the short arm of the lever, though its length may exceed that of the radius of the wheel.
Power and speed are interchangeable. The shorter the arm of the crank, the greater the weight requiredto balance the long arm at the rim of the wheel (an imaginary line). If the pedal crank is lengthened, it will require less power to move it. At the same time the foot, following the crank, describes a larger circle for the distance travelled by the rear wheel. The crank lengthened, the power is diminished, demanding increased exertion to follow it, the foot travelling at a rate determined by the distance to be traversed.
When the hub rests on the axle of the wheel, there is considerable friction to overcome in the entire length of the hub, the friction, or ability of the wheel to turn, depending on the amount of axle surface. The axle, therefore, becomes heated when the air cannot readily reach the surface to convey away the heat generated by friction.
Weight may be balanced and supported on a point; when weight rests on a sphere, only a point supports weight. By surrounding the axle with balls, the weight is taken from point to point on each ball, and a circulation of air allowed. The weight, carried from ball to ball, gives the advantage of a larger cooling surface in a confined space, while the weight and friction are applied directly to a very limited area. Each ball is also an axle in itself, and carries the weight, and passes it on to the next ball. The balls act as lubricators, preventing the moving surfaces from contact.
The problem of speed produced by power means that speed is obtained at the expense of power expended. The relative size of the sprocket-wheels determines the relative speed of the cranks and rearwheel. To get the greatest speed with the least power possible means diminished friction and lessened weight. The band or chain complies mechanically with these requirements, permitting a certain amount of play, which lessens the danger of sudden strains and jars, and supplies the power to the rear wheel with the least possible loss by friction.
“Scientific American Supplement, No. 1025,” August 24, 1895.
Rating wheel by the amount of progression for each turn of the crank (pedal), the following table, compiled by Henry Starkweather, will be found of advantage:
The following table, from the New YorkEvening Post, shows the gear according to the number of teeth on large and small sprocket-wheels: