CHAPTER VII.

HUBS, SPOKES AND RIMS.

The wheels of the 1898 bicycle do not present any very remarkable or striking novelties in construction. The old style of slender cylinder hub with broad flanges has, however, disappeared, and the tubular or barrel hub, with or without flanges, is the only one in use. But before surveying the state of the art for this season let us take a look backward and see what led up to the present types. At the Crystal Palace, London, England, was exhibited in 1889 a bicycle that was built by Gavin Dalzell, a Scotchman, some time previous to 1846. This was described as “being wonderfully strong, especially in the wheels,” these seeming to have stood the ravages of time and rough usage much better than the framework. The rear wheel, or driver, was of wood shod with iron, about 40 inches in diameter, and had twelve spokes, each about one inch in diameter. The front wheel was of similar construction, but only about 30 inches in diameter. The wooden velocipede of 1866 usually had wooden spokes and flat iron tires, and about that time a very crude high wheel was built in England by S. Madison, and this in 1868 was improved upon by Edward Cooper. In 1869 the bicycle called the “Phantom” was put upon the market. It had wooden rims with rubber tires nailed on. On the inside of the rim were staples, through which the wires were passed and screwed at the centre of the wheel. It was really the first practical suspension wheel ever built, its one fault being its liability to get out of order and the inability of the mechanics of that time to true it up again. James Starley brought out a bicycle a little later called the “Ariel,” which had “lever tension” wheels and was popular. It had double wire spokes and steel rims, and at the axle of each wheel was placed a lever bar.

He next designed one called the “Spider” and for a long while all bicycle wheels were therefore called spider wheels. In 1876 Singer’s “Challenge” appeared in London, which had lock-nut spokes, with a nipple attached. Nipple and lock-nutted spokes long outlasted the construction of that day, and they were certainly very far better than the butt-ended direct spokes used later on.

The first tangent spokes were those made by the Coventry Tangent Company, in England, and placed upon their bicycles and tricycles. A singular fact is that for some years after that, however, tangent spokes almost wholly disappeared, not only in this country, but in England, and, while we were importing English safety bicycles, all of them had direct spokes; but the first American safety bicycle built, the Victor, had tangent spokes, and so had the high wheels previously made by the Victor Company. In England, until two years ago, direct spokes were very largely used.

THE “SUSPENSION” WHEEL.

Here American makers used direct spokes at first, but at present all the American makers without exception use a tangent spoke, and there are indeed very good reasons for the use of the tangent spoke in a suspension wheel, which is a structure radically unlike the ordinary wagon wheel. Any vehicle wheel receives the load of the weight carried directly at its hub, through the axle, and this weight, of course, tends to bear the hub down to the ground. The wagon wheel has stout spokes, as they are planned to sustain the crushing downward strain; this strain is wholly borne by the few spokes at any particular instant below the hub, the rest of them at that instant having no work to do. In order to avoid the weight and clumsiness inevitable if the bicycle wheel were made to carry the load in this way, the load is “suspended,” in effect, instead of being above and upon the spokes. That is, the load applied at the hub is hung from the few spokes which at the instant are directly over the hub; the pull down on these spokes tends to depress the upper part of the rim and thus to flatten down the wheel from a circular to an elliptical shape; but this flattening is resisted by the spokes which are then horizontal, or nearly so, and thus the wheel retains shape. The thin wire spokes, which would instantly double up under a “crushing” strain, resist tremendously the tensile pull. Imagine a thick-spoked wheel with all spokes gone except those in say an eighth of its circle directly underneath the hub and you have the ordinary wheel; then imagine a bicycle wheel with all spokes gone except a few directly above the hub and the few horizontal ones on each side of the hub, and you have the “suspension” wheel illustrating its own principle, it being supposed that the wheel in each case is not moving but simply holding up its load.

The wagon wheel is “dished,” that is, the spoke ends at the hub are not quite in the same plane with the rim; the spokes are also often “staggered,” that is, one-half are in one plane at the hub and the rest in another, the object being that the wood may have room to expand and contract somewhat, under changes in moisture, without putting the wheel out of shape. The suspension wheel is also dished, but the dish is a double one, the wheel in section being like two capital V’s, end to end, being somewhat wide at the hub, the spokes being carried from the rim alternately to one side of the hub and the other. The object is to strengthen the wheel laterally, for if it were made all in one plane from top to bottom it might sustain a heavy load in a vertical direction, but would twist into pieces under the first side strain. This explanation may not only give the uninitiated a better idea of bicycle construction but may illustrate the fact that new problems have had to be met and new devices thought out and worked out at every stage of that construction.

CONSTRUCTION AND STRAINS OF HUB AND SPOKES.

The pressure applied on the pedals of the bicycle causes a transverse strain on direct spokes which sometimes causes them to snap at the rim or hub; but spokes which are set at a tangent to the hub receives this strain directly, and in the tangent-spoke wheel, where the spoke is bent or hooked in order to pass through the side of the hub, it is necessary that the very best material and workmanship be used to prevent it from breaking at this point. The tangent-spoked wheel being almost absolutely rigid, is the best hill-climber, for there is no waste of power as in the direct-spoke wheel, the transverse strain on the spokes of which causes a certain amount of “give.” On the first safety bicycles built in this country 30 and 32 inch wheels were used. Afterward we settled down to the use of 28-inch wheels as a standard. There is now, however, a slight tendency to reversion toward using 30-inch wheels. The makers of the Cleveland wheel have announced that they will market a bicycle having 30-inch wheels. Probably the only reason for this step lies in the dropped crank-hanger fad; so that, by using larger wheels, they can still maintain the upper tube horizontal, and get the required drop of from three to four inches. Viewed in another aspect, however, it will be found a source of annoyance and expense to the makers and riders as necessitating an extra stock of spokes, rims and tires to fit the same, and where they are not to be had promptly delays will be sure to occur in repairing. The ruling size of wheel is not arbitrary, but has been arrived at as the best net adjustment of all the conditions, and any change to what has been thoroughly tested and abandoned is to be strongly disapproved, unless (which is not the case in this) substantial reasons can be shown.

Few people realize the torsional strain exerted on the rear hub when full power is applied to the pedals in climbing a steep hill where the momentum is not sufficient to carry the rider far and where the pull is more or less continuous on successive groups of spokes as the wheel revolves. In addition to this pull on the spokes is to be considered the weight of the rider, the greater proportion of which is sustained by the upper half of the rim and the corresponding spokes and not by the portion of the wheel nearest the ground as just explained. It will be understood that each group will be subjected for an infinitesimal space of time to a maximum pull as the chain passes over the sprockets, the strain being accentuated at each downward stroke of the pedals, so that a single spoke when at a very high tension as compared with its neighbor frequently snaps when directly in line with the chain at the proper instant of time. Originally all hubs were made of what is known as gun metal, the flanges of the hubs were very thick and tapered toward the centre of the hub. They were made in this manner to provide sufficient room for tapping and threading the hub flanges so that the direct spokes which were in use at that time could be directly threaded into the hub.

The 1898 tubular and barrel hubs are, of course, the result of many processes. Some of them are turned whole from bar steel; others are stamped out of sheet metal; some of them are formed out of tubing, and a few of the cheaper makers use malleable iron or cast steel for this purpose. All of the spokes used are made of either a special drawn steel wire or a piano wire. They all possess great torsional or twisting strength, and the tensile strength or stretch is from 500 to 800 pounds. They average in gauge of thickness from 13 gauge, which is expressed by the figures .095, to 15 gauge, which is expressed by the figures .072. Front wheels have from twenty-four to thirty-six spokes and rear wheels from 28 to 40 spokes, and while it is true that all the makers now use a tangent spoke there are a great many variations in its use. The majority of them tie their spokes to each other where they cross. There are a great many of the makers who do not tie them at all, there being some difference of opinion as to the benefit to be derived from this treatment.

Those in favor of tying spokes say that tying two or more spokes together at the crossing some distance above the hub shortens the leverage from the rim and practically gives the wheel an additional hub; that they are also stiffer against side or lateral strain, and that the only good tangent spoke is one that is tied at the crossing with its mates. Those who are opposed to tying spokes say that tying them together makes them too rigid and inflexible, and that the process of wiring them and soldering them together has a tendency to crystallize the spokes at this point owing to the heat required to solder them. This part of the argument, however, has been met by not wiring and soldering the spokes at the crossing, but by pinching on them at this point a metal clamp such as is used on the Humber wheel. The opponents of tying the spokes assert that the very stiffness and rigidness which the wheel possesses when the spokes are tied has a tendency to also crystallize them at the hub flanges as well as cause them to break. It may, however, be here stated that the pneumatic tire acts as a buffer, and that the use of heavier rims and more spokes, which are prominent characteristic features of 1898 wheel construction, insures the whole wheel a greater factor of safety than heretofore known in construction, and therefore less liability to get out of true.

The Raleigh cycle, an English production, and which came into prominence in this country because it was Arthur Zimmerman’s great mount, had wheels in which two-thirds of the spokes were direct from hub to rim, and the remaining third were crossed at a tangent. It was, however, a sort of a compromise between the direct and tangent spokes, and ultimately led the makers to use tangent spokes only.

THE WOOD WHEEL.

A number of attempts were made a few years ago to introduce hickory wheels in place of the wire suspension wheels, among the most notable being a bicycle built by Sterling Elliott, and called the “Hickory.” The frame was built of tubing as was usual, but the wheels—hubs, spokes and rims—were made of hickory, the spokes being known as radial spokes. In order to maintain its rigidness and to carry the pneumatic tire the rim was surrounded by a metallic band in which the tire was placed. The public did not take to this style of bicycle wheel, and their manufacture was discontinued, not however before Mr. Elliott placed a pair of these ball bearing hickory wheels with pneumatic tires on a high wheel sulky, which had been converted to carry these wheels. The result was astonishing, and today no other wheels are used on sulkies but 28 and 30-inch bicycle wheels with ball bearings and pneumatic tires, and the result of their use had been that the times of the trotting horses have been reduced six to ten seconds per mile. Of course the present type of sulky is built specially with arched axles and frames to carry these wheels, and the old high wooden wheel is as rarely seen on the trotting track as the good old “ordinary” is seen on the bicycle track.

Hubs using a spoke having a hooked end with a rivet head on the end thereof, which are drawn through the holes in the flanges of the hubs are not as popular as formerly, a great many of the makers having departed from this method, now using a spoke which is straight from the hub to the nipple. They claim for this method that the absence of the bend in the spoke minimizes the liability of crystallization which is so apt to exist in spokes of the bent variety. This style of direct tangent spoke was first shown in this country in 1892 by the makers of the Liberty, and among the most prominent users of this style of hub are the makers of the Spalding, Victor, Crawford and the Iroquois, and which are almost duplicates of the Liberty hub. The Keating differs somewhat from these, inasmuch as the projections from the sides of the flanges are not opposite each other, but are placed alternatively to receive a single spoke. The Liberty hub may be best described as follows: It is a one-piece hub, with lateral projections from the sides, or flanges, and these projections are drilled to carry the heads of two straight spokes, each spoke running in a straight line to the opposite side of the rim. The usual style of hub has a plain circular flange with holes drilled in it to receive the spokes; this makes it necessary to bend the spokes at a right angle at the end, where they are inserted over the face of the hub. This sometimes rendered them liable to break, and, therefore, what is known as the direct tangent spoke was invented.

In this method of construction the hub end of the spoke is not bent, but has a head made upon it like that of a rivet; the strain comes in a direct line from end to end of the spoke, and the entire spoke is in tension. The early makers of direct tangent spokes found it necessary to make these of a somewhat heavier and softer wire than the tangent spokes which were bent at right angles to form a hook. The use of this soft thick wire proved rather objectionable, as it was with difficulty that the wheels could be kept true, and the spokes were apt in compression to slide through the end of the flanges on the hub and make a noise. However, all makers who use direct tangent spokes are making them very much thinner than heretofore, and of a harder quality of wire. In fact, the makers of the Crescent (also having these direct spokes) use probably as light and as thin a wire as any of the makers who use a spoke with a bend at the end. The makers of the Wolff-American (who are also renowned as great makers of wire) claim that there is no necessity for the use of a direct tangent spoke if the proper quality of wire is used for making the spoke which has its end bent at right angle, and that while it is undoubtedly true that the spoke bent at right angles at the end does stretch its fibres on one side of the bend and compress them on the other, still, if the spoke flanges and spoke holes and the nipple holes at the rim were only drilled at a proper angle to each other, there would be no danger of a broken spoke. All 1898 spokes are swaged and butt-ended. Formerly spokes were known as upset and butt-ended. Upsetting a spoke consists in heating the ends and driving it backwards, thus making it thicker than the rest of the spoke. The objection to this practice consisted in its tendency to crystallization where the “upset” ended. Swaging a spoke consists in leaving the butt ends of the spoke the original thickness of the wire, and reducing the diameter between the ends by a hammering process in a machine built for the purpose, to a gauge or two smaller than the original thickness. This method of making spokes reduces the weight, leaves the heavy portion where it is most needed, and adds great tensile strength to the spoke. In making a spoke by this method the wires are at first made somewhat shorter than the length required, as the swaging has a tendency to draw them out in length, and in the best of modern practice of spoke making the threads are rolled on by machinery instead of having them cut on by a die, as formerly. The rolling process has this advantage, that it does not reduce the diameter of the spoke and cut away so much material as the die threading process.

VARIOUS STYLES OF HUB AND SELF-OILING DEVICES.

The makers of the Sterling, who have always used a direct tangent spoke in connection with a hub having a corrugated flange, show a new hub this season. It is machined from a piece of bar steel. The flanges or teeth are somewhat like a small rear sprocket. They are, however, of the double hollow construction, and on the rear hub on the sprocket side part of the flange is cut away on the outside, leaving a large opening in the tooth, which sits between the teeth of the sprocket wheel, so that a spoke can be readily inserted without removing the sprocket wheel, and through the first-mentioned hole the spoke is pushed forward and upward through a buttonhole, and is then slid in a T-slot either right or left to its seat, each tooth in the flange thus carrying two spokes, one to each side of the rim. On the left hand side of the rear hub the construction is reversed, the flanges not being cut away as on the right hand side, and the spokes are inserted through a similar opening as before described on the inside portion of the hub and flange. On both sides of the front hub a similar construction is employed as that in use on the left side of the rear hub.

The Windsor hub is of the corrugated pattern, having a double flange in which the spoke holes are drilled, and with a buttonhole device for inserting the same.

The Crescent hub is built with a straight flange over the body of the hub, and this hub flange is turned over, forming a wide bearing surface, which is drilled for the spoke holes, and underneath this outer edge a buttonhole device is placed in the body of the flange by which the spokes can be easily removed and replaced, and without the removal of the rear sprocket.

The Columbia hub has a series of studs inserted in the body of the hub and through these studs holes are drilled, and the direct tangent spokes are inserted therein.

The Eclipse hub is turned from the solid bar of steel and has two flanges at each end; these flanges have alternate slots and holes. A T-head spoke is inserted by passing the head down the slot and pushing it sideways down the opposite hole in the adjoining flange.

The Wolff-American hub, which was one of the first large tubular hubs shown in this country, is made of steel tubing without either projection or flanges, but has a buttonhole device which greatly simplifies the replacing of spokes. Inside the hub and underneath the spoke holes is placed a dust-proof ring which prevents the intrusion of dust into the bearings. They use a hollow axle containing an absorbent wick saturated with oil. In the axle over the wick is a minute hole on each side, through which the oil is drawn by centrifugal force by the revolving of the balls, and thus is supplied to the bearings in the crank-hanger in the same way and automatically the supply is regulated by the demand.

The makers of the Cleveland also have an automatic oiling device on their hubs. The wheel and crank axles are tubular and hollow. This space forms an oil receiver. In order to prevent the oil from escaping from the hollow axles the end is plugged with a screw; under the head of the screw is a piece of packing, making the joint perfectly tight. The flow of oil is regulated by wicking drawn through small holes drilled in the axles close to the bearings. These holes are plugged so tightly that the oil will not escape when the bicycle is not in use. The moment the wheel begins to revolve capillary attraction produces a drop of oil at the end of the wicking.

There is this to be said in favor of both the Wolff-American and Cleveland devices that there is no danger of losing any oil cups, and that after a long, dusty ride oil has not surrounded the hubs and crank hanger bracket to which the dust can be attracted, and the bicycle is therefore very much easier to keep clean. The makers of these styles of automatic oiling devices claim that they will carry a season’s supply of oil, but even if this should not prove to be true, it is only necessary to lay the bicycle on its side, remove the plugs in the ends of the axles and pour oil into the reservoir.

WOOD RIMS.

As has been already noted in the article on tendencies, the wood rim has undisputed possession of the field, not a single American maker cataloguing a steel or other metal rim. Even the makers of the Eagle, who formerly used an aluminum rim, now offer it as an option only, and show all their samples with wood rims, and this may again be regarded as a reversion, the original type of the old “Dandy Horse” velocipede having been built with wood rims and shod with iron, the only difference now being that we use wood rims shod with air, and when the “good old ordinary” came in vogue steel rims were introduced. On the ordinary, however, which had only small solid tires, the rim was a narrow grooved one, and possessing, as it did, very little lateral strength, it had a great tendency to buckle under the force of a blow or a collision, and when the safety came in vogue this same idea of rim construction was carried into it. An improvement was made, however, in their construction in making them of a double hollow construction which increased its lateral resistance, but in case of accident made them extremely difficult to repair. A little later, when the cushion tire arrived, the single rim and the double-hollow rim were used, making them, of course, of a larger cross-section to fit the tires used, and when the pneumatic tire was invented the steel rims first used very much resembled a band of hoop iron used on an ordinary washtub. Afterward double-hollow rims were used on bicycles with pneumatic tires, and single rims which were fluted or corrugated in order to give them additional stiffness were also used. In 1891 McKee & Harrington of New York City, the makers of the Lyndhurst, introduced a bicycle having wood rims. These rims were made of second-growth white ash and were of the single-piece variety, joined together with a long, tapering “skive,” and the entire rim and joint were covered with natural color Pongee silk, which was glued on, producing a watertight rim. This rim was the production of Mr. Charles Harrington of this firm, who for many years before entering the bicycle business had been known as a practical wood worker. Makers and riders were very skeptical of the value of the wood rim, but after a few well-known racing men had won a few track and road events on them and the wood rim had shown its utility and value by its increased resiliency and speed, and that it was stronger across its lateral plane than a steel rim of any type could ever hope to be, and with its non-liability, therefore, to buckle in a collision, it became a popular thing, and in less than two years, as has been seen, it has completely routed the steel rim out of the American market. In England, however, owing to the large use of the detachable tire and the moist climate, its advance has not been so rapid, but it is coming along even there, and it bids fair to supplant the steel rim there in another season or two. One-piece rims are not so largely used as heretofore. The laminated rim as now made, which was originated in 1893, seems to be the most popular one on a majority of the high cost bicycles on the market. It is to be noted, however, that the rims of this season, almost without exception, are broader across their face and thicker through in section, which is an especially good feature, inasmuch as it gives the tire a larger and firmer bed to rest upon, so that it is not so liable to be cut by the edges of the rim. Of course, making the rim broader and thicker and heavier takes away some of the points which were formerly used in its favor, notably those of light weight and resiliency. The up-to-date wood rim more closely approaches in weight the lightest possible form of steel rim, and it is a notable fact that the wood rim is the only prominent contribution in bicycle construction that America has presented to the world, and there is good reason for this, however, because our Yankee and our Western wood workers have long been famous for their progress in the art of wood working and wood bending. One of the most famous wood benders is Mr. H. H. Shepard of New Haven, Conn. In 1889 he had the temerity to send to the Paris Exposition, in the care of a French exhibitor, not wishing to go to the expense of a personal representation, some samples of his wood bending. These samples came in direct competition with the great Vienna, German and French wood benders, and although Mr. Shepard, as before stated, was not personally represented, to his great surprise the Commissioners unanimously awarded him the only solid silver medal for superior excellence in that department.

This same Mr. H. H. Shepard (who, by the way, is a six-footer and bearded like a patriarch), in a lecture in New York City on wood-bending before the master mechanics of the Carriage Makers’ Association, placed his audience in good humor with him when he declared that his earliest recollections of bending were when, while a boy, his mother bent him over her knee to keep him straight. The Shepard is a one-piece wood rim of second growth white ash. The ends are butted together and an ovoid piece of hardwood is inserted over the butt ends on the inside of the joint. This insert extends about three inches each side of the butt-ended joint and is flush with the remainder of the rim. These rims are bent by compressing the inner surface in a hydraulic press without stretching the outer periphery of the rim. This method shortens the inner surface about six inches, thereby greatly toughening the inner surface of the wood. The average weight of the steel rim formerly used was about 24 ounces. The average weight of the wood rim used for a cemented-on tire as first made was about 14 ounces. The average weight of the wood rim in use today is probably about 18 ounces.

VARIOUS MAKES OF WOOD RIMS.

Another popular rim is called the Winona. The process of making the Winona rim is as follows: There is about six inches difference in the circumference between the inside and outside of the rough rim. The bars being straight before they are bent, it is obvious the inside must stretch or the outside upset. The process used prevents stretching of the outside fibre of the rim, and actually upsets the outside as well as the inside, thereby interlocking the entire fibre and doubling its original strength. They use a plain beveled dovetail joint. They also make a laminated rim, and what they call a screwed rim. This rim has screws at stated intervals running crosswise of the rim, coming just under the seat of the groove, as the greatest strain on the rims is caused by the spokes, which sometimes result in splitting the rim. They have undertaken to overcome this, or, rather, to strengthen the rim by putting in these screws. The illustration shows a sectional end view of the rim and the manner of inserting the screw from side to side. The Winona rims are made of butt cuts, and they use what is known as a second cut rock elm only for their rims. Rock elm has dark streaks running through and is dark in color, differing, therefore, from second growth white ash, which is very light in color.

A well known wood rim is that known as the Plymouth, which consists of a single piece of rock elm bent, jointed and turned on a lathe. The joint in the Plymouth rim is so constructed that the ends come together square across. It consists of a series of tongues and grooves interlocking, the tension of the spokes making them tighter instead of straining them apart. One of the special features of the Plymouth rim is the fact that the spoke holes are eyeletted and are thus made waterproof. The illustration shows their reinforced joint.

The Kundtz is known as a double reinforced rim. It requires two rims to make one, and the manner of cementing one rim into the other, with a section of thin wood between them, which has its grain running crosswise to the two main sections, as shown in the illustration, produces one of the strongest wood rims made. Another improvement in this make is the fact that its glued joints are not exposed to the weather, which has been considered a detriment in building up rims of the old style.

One of the most popular rims is that which is known as the Fairbanks-Boston. A laminated wood rim is one, as is now quite generally known, formed of curvilinear maple segments, indissolubly cemented into perfect unity under enormous hydraulic pressure, which, because of this principle of jointure, remains perfectly true both laterally and in periphery, while the transverse grains of the adjoining segments or laminæ absolutely prevent splitting along the line of spokes in the impact of collision or shock. The fact that no single joint extends through the rim effectually overcomes any tendency to break off in any direction or manner. The makers use three curvilinear segments of Pennsylvania rock maple. Each segment is planed on both sides to a thickness of mathematical exactness throughout the entire length, thus insuring absolute unbroken contact when cementing to the adjoining segments.

The overlapping ends of each segment are by special machinery then “scarfed” to feather edges, obtaining laps equal in length tapering on an angle which experience has proven correct. By this process of bending the rims do not require steaming, which disintegrates the fibre of the wood, and in cementing the joints the three laps are placed at points of the circumference of equal distance apart, rendering the tensile strength absolutely uniform in all parts. In compressing the segments of the rim together hydraulic pressure is applied to the periphery of the rim after the application of the cement. An enormous pressure is applied equally at all circumferential points, and it is maintained until the cement has completely solidified the three independent segments into the form of a permanent circle. They also make what is known as a covered laminated rim, the enveloping fabric, which is a special quality of pure Irish linen, fitted exactly on the rim and secured permanently with liquid cement, and it is estimated that enclosing the rim in this manner imparts at least 30 per cent. to its strength, with a corresponding increase in is resiliency, and these rims are therefore recommended in damp climates, and for use on tandems and other multicycles. All the makers furnish their rims in a natural varnish, and also stained in imitation of rosewood and other woods, and many of the makers in addition to this furnish the rims painted and striped in different colors, in many instances matching the colors of the enamels used on the frames.

At the ’96 Cycle Show papier-maché rims were shown, for which great claims were made and a great deal expected, but none of the well-known manufacturers adopted them, and the company that brought them out has since gone out of existence. Trials within the knowledge of the writers proved that these rims as made then were not practical.