The Cycle Industry/Chapter 5

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In writing a chapter on the production of bicycles under the above heading it is possible to describe each process in detail until one would have quite a large book on that subject alone. It will be readily understood that in a book of this size such microscopic attention is impossible. It is, therefore, my intention to take the reader a personally conducted tour round a large cycle factory, commencing at the stores and finishing at the loading bay of the packing department, and refer briefly to each process in passing. We will imagine, therefore, that the entree has been secured to look over a cycle factory where everything except saddles, handles, tyres, and toolbags, is produced on the premises and assembled to make a complete bicycle. Arrived at the rough stores we find bins on the floor and racks lining the walls right up to the roof. In the racks and bins are steel tubing in multiple lengths of several feet, ready for cutting up into frame tubes, bars of steel of various sizes for making into cups, cones, and spindles for hubs, castings and stampings for frame lugs, spokes in bundles, steel and wood rims of various sizes, and of course, the usual stock of steel and other stores required by the factory millwrights for engineering purposes other than the actual construction of the bicycles.

Each stores has its own storekeeper, a clerk who specializes in organizing his department so that there is not a superfluity of one article and a scarcity of another. The various articles as they are delivered are counted, weighed, or otherwise reckoned, and a
The Cycle Industry (1921) p47.jpg

Fig. 14
The hoods in the background are arranged over the brazing hearths to carry off the fumes

record on cards of the number or weight is placed over each bin or rack. As the articles are requisitioned by the factory management, the numbers or weight extracted from bins or racks are noted on the cards and the supply made up from outside, the aim of a good storekeeper being to maintain a certain high-water mark, below which the stock is not permitted to fall.

Very little of the material issued from a rough stores ever comes back again, but the state of things in the finished stores is different. Here, again, are bins, fixtures (a series of shelves in wood or iron with vertical divisions like large pigeon holes of a desk), and racks, but they all hold finished or partly finished parts. Thousands of axles, cups, cones, balls, nipples, nuts, screws, etc., will be seen all neatly arranged and docketed, the racks hold finished frames, forks, saddles, mudguards, brakework, etc.

The procedure here with regard to issuing the parts is that a requisition comes from the office management, sales or other department, to put through, we will say, 100 machines of a certain model (the requisitions in some factories are much larger, but we will take the above figure as an example). The storekeeper in the rough stores issues to the machine shop and frame builders 100 sets of frame lugs, 100 sets of tubes cut to length and mitred, enough tube to make up 100 seat pillars, fork-sides, and crowns for 100 forks, 200 rims, the necessary spokes, and so on. These are made up into complete frames, wheels, forks, etc., and go when completed to the finished stores; here they are viewed, and re-issued to the finishing department with the necessary tyres, saddles, handles, brakework, and so on.

Each time the parts enter the stores from the factory the work done is entered and the operatives are given credit for the work done, and the cards or books pass along to the wages office, where those who are on piecework rates are credited with the various amounts, and paid weekly, or the amounts are allowed to accumulate for a period settled between the shop stewards and the management, and the workpeople draw a weekly wage on time clocked, balancing the account at intervals.

In very large factories there may be a separate stores for tyres, another for brakework, frames and forks, and another for wheels, each floor or department having its own stores. Whether this arrangement or the one outlined is followed, the procedure is practically the same as regards the checking and recording of the work as it passes through the various processes.

Frame Building. We now enter the frame building shop, where the lugs and tubes are built up to make the frame. The lugs, in the form of castings or stampings, have been machined in the machine shop. This consists of placing the lug on a jig (a tool that holds the lug at the correct angle for turning, drilling or boring) which is bolted to the lathe or drilling machine which forms it. Iron castings are hollow and have little superfluous metal to be removed, stampings are solid and the steel to be machined away is considerable. Modern methods, however, allow either to be dealt with with practically equal rapidity, and when completely machined each lug weighs only a few ounces. Some firms, notably the Raleigh and Rudge-Whitworth, use pressed steel lugs, a process which presses the lug from sheet steel, which is folded, so to speak, between dies in a very powerful screw, or other type press. The frame builder is provided with a sort of master frame, called a jig, on which he assembles the lugs and tubes roughly, and when they are positioned by stops on the jig he turns screws which lock the parts while he drills holes at each joint for conical metal pegs which keep the tubes in place while the joints are brazed. The frame builder is responsible for the correct alignment of the frame. When the joints are pegged he passes on the frame, or it is taken for him, to the brazing shop.

Brazing. Brazing is done in different ways in different factories, some adhere to hearth brazing, others use the more modern liquid brazing. Brazing is really soldering with hard brass, as distinct from soft solder. In hearth brazing an open fire of "breeze" (small coke) is kept at a high temperature by allowing a pressure coal gas flame to impinge on the glowing coke. The joint of the frame is pushed into the fire, but before the frame builder parted with it he had coated the two metals to be united with a flux to facilitate the flow of the brass.

The brazer has in his hand a "stick" of brass or a spoon filled with brass dust called "spelter." When the joint has reached the correct temperature he feeds it with the "stick" or "spelter," and the flux carries the molten brass into the joint. Parts on which the brass should not adhere are specially coated to prevent the molten brass from sticking to the steel or iron.

The other process, called liquid brazing, consists of placing the joint of the frame or other part into molten brass spelter, heated in a special kind of gas oven. The part is withdrawn when the brass has run into and between the two surfaces to be brazed.

After brazing, the frames and forks go into vats and are pickled. This is a bath of corrosive liquid that attacks the rough spelter and softens it previous to the filing up of the joint, or, if the firm has a sand blasting shop, the rough spelter is blown off by a strong current of air, in which sand or shot is carried, and forced on to the joint from a flexible pipe held in the operator's hand, the frame, fork, etc., being supported on a bench. The sand blasters wear masks and cloaks which make them appear like the pictures of torturers in illustrations of the old Spanish Inquisition. From the filing up or sand blasting shops the frames go to the iron polishers. These men or women (for female labour is employed for polishing) hold the frames on grinding wheels or in some cases endless belts coated with emery, and they grind or polish the whole frame till it is bright and very smooth.

The frames and forks then go to the enamellers, a part of the factory we shall visit presently, when the other parts are ready for the painting process.

The Machine Shop is the department where all the parts that require turning, boring, milling, or profiling, are machined, as the various metal removing processes are termed. Here we may see turret lathes, forming hubs from bar steel, milling machines, forming the teeth on sprocket wheels for the reception of the driving chain, milling or profiling cranks, turning and boring frame lugs and fork crowns, profiling the internal parts of free wheels, and a hundred other small parts that go to make up brakework, pedals, etc. Small screws, nuts, steps, bolts, etc., are usually bought from specialists who can make these parts from steel bars in automatic lathes at very much lower prices than can a cycle manufacturer, who would have a comparatively few of each to make before he had to change the tools in the machine. Hubs are made from stampings and castings as well as from bar steel, opinion being divided as to the economy of the three processes.

The wheel building is often done by women and girls. The steel rims are drilled or punched in special machines which space out the holes evenly, for 32, 36, 40, or 44 spokes, according to whether they are to be used in front wheels, back wheels, racing or roadster machines. The spokes of steel wire are supplied headed, bent, and screwed. Where the screwing is rolled on instead of being cut with dies, each spoke is apparently only touched against the rolls and the thread appears. The rolling leaves the skin on the metal and enables a lighter wire to be used, because it does not cut through the skin and weaken it.

The nipples are of brass or gun-metal and the washers of steel. The wheel builder laces the spokes through the holes in the hub flange, then through the holes in the rim and slips a washer and nipple on the end of each. When the wheel is loosely assembled it has to be trued. This is a process that requires skill to obtain the same degree of tension on each spoke and is effected by screwing the nipples down the spoke with a special nipple key turned by hand or power on the end of a flexible shaft. The final truing process is done entirely by hand.

Brakework and mudguards are usually made up in a separate shop or on a separate bench. The mud-guards are rolled by specialists from flat strips of thin steel and are delivered to the makers bright, ready for attaching the stays and bridges. The latter are the strips of metal laid across the mudguard and riveted to it, or, in some cases, electrically welded or brazed. The eyes are formed on the stays or they may be separate parts brazed or welded to the stays.

The brakes vary a good deal on different machines, but on high-class bicycles they are usually operated by Bowden cables and wires which are concealed in the handle-bar and are operated by inverted levers underneath the hand grips. The Bowden mechanism obviates all bell cranks, rods, and other levers because it conveys a direct pull to the brake while passing around angles which are not too acute to prevent free sliding of the wire inside the cable.

Another popular type of brake is the roller lever brake. This is usually made up by the cycle maker to suit his own models and consists of a lever placed each side of the handle-bar which rolls or turns in a bearing. At each end of the lever there is a crank which pushes down a rod in communication with the front or rear brake shoes. The handle-bar brakework is usually assembled on the bar ready to slip into the machine in the finishing shops.

Handle-bars are largely bent by specialists, but some firms make their own. The process is usually to bend the touring patterns cold by inserting a spring mandrel in the straight tube, to prevent the metal kinking or denting, and withdrawing the mandrel by unwinding it. The curly types of handle-bar affected by racing cyclists often have to be filled with sand or rezin prior to heating and bending, the "loading" material, as it is called, being afterwards melted and poured out.

The stem of the bar may be inserted in a "T" lug threaded on the bar, or it may be made entirely from steel tube. In the latter case some skill is required to wrap or "lap" the top of the split stem around the bar to make a neat joint. Seat pillars are nearly always made by the "lap" joint method; a good bicycle may be often known by a careful examination of these joints, because a maker with a reputation employs men who can make these joints practically invisible, whilst the shoddy ones have rough edges and imperfectly made joints.

As the polishing, plating, and enamelling have to take place before the machine is assembled, we will visit those shops before going to the finishing shop, the term applied to the bay or floor, where the bicycle receives its final touches. Polishing is a process that consists of holding the parts, large and small, on wheels of various diameters and widths that have on their edges or peripheries leather coated with emery dust which adheres to glue with which the wheels are coated. The final polishing (plate polishing) is done with wheels made of discs of calico, which assume a certain rigidity suitable to the work when they are revolving at high speed. The disc or wheel of calico discs is called a "mop" and the process is termed "mopping," to distinguish it from the coarser polishing. The calico is impregnated with grease and tripoli or rouge powder and also powdered lime or whiting.

The polishing shops resound with the whir of the polishing lathes and the air is largely impregnated with dust of steel, emery, glue, and leather. The operators are supposed to wear respirators, goggles, etc., to protect their lungs and eyes, but more often discard them when the foreman's eye is removed—one instance of where a paternal Government legislates for the workers' welfare without very much gratitude on the part of the operators.

Practically all parts come to the polishing shop because, without a highly polished surface on painted and plated work, imperfections would be very much magnified when the machine was turned out.

When the parts leave the polishers they are not chemically clean, and if they were immersed in the plating bath or enamelling vats before being cleansed to remove all trace of grease, the plating and enamel would peel off. They are therefore thoroughly scrubbed with chemicals to remove the grease, and when dry are placed in plating or enamelling vats.

The former is, of course, an electrical process, and consists broadly of depositing metal (nickel) from a slab of the nickel to the steel. Various methods are used, and some highly ingenious machines have been devised for rapid plating of small articles. The latter are strung on wires like the Chinese carry money, and hung from metal rods which are charged with an electrical current of low voltage. The other pole of the electric current is connected to the nickel slab (anode) and the nickel passes from the anode to the steel to be plated. When the parts emerge from the bath they are dull plated and resemble unpolished aluminium; therefore, before being sent to the finishers or finished stores they have to be polished again on the before mentioned calico mops or wheels.

The polished work to be enamelled has to be chemically treated to remove all grease, and in some instances baths of heated patent liquid are employed. Some makers are content to clean the parts with a grease removing spirit, like turpentine. When clean, the frame, fork, mudguards, etc., are either dipped in liquid black enamel and hung up to drain or liquid enamel is poured over them. When the superfluous enamel has drained back to the sump of the pan the parts are lifted on hooks (the enamelled surface must not be touched with the hand) and hung in gas heated stoves, where they are baked at a high temperature for a few hours. The very best bicycles receive at least three coats of thin enamel and are stoved between each application. The resulting surface, when cold, should resist blows with a wood broom handle without cracking.

Enamelled and plated parts are handled by the assemblers in the finishing shops in different ways, according to the organization in different factories, but a common method is to have an iron pillar standing up at the edge of the bench, the steering tube of the frame, minus the fork, is dropped over the pillar and the frame is free to swing. The finisher scrapes superfluous enamel out of the bottom bracket threads, and other parts where bearings, etc., require to be fitted, runs a dummy, or easy fitting tap, through the threads, wipes a little oil on the threads and screws in the bearing cups, fits the axle, cotters on the cranks and chain wheel, inserts the seat bolt, ball head cups, attaches the rear mudguard and brake work, and slips the rear wheel into the forks. All this sounds very easy, but in the best work there are small adjustments to be made. Sometimes the plating has adhered where it is not wanted, and nuts and bolts will not screw together easily. To ease the threads the finishers use a hand tapping machine, and a similar hand machine for screwing the outsides of bolts, etc.

Finally, the chain is put on and adjusted, the pedals screwed into the cranks, and the finisher turns his attention to the front forks and wheels, which have been gradually growing to separate front units complete with their mudguards. The rear portion, frame, rear wheel, etc., is lifted off the bench support and dropped over the front fork stem, the whole machine is twisted upside down and the balls of the steering bearings are poured in from a little tool that scoops up and counts the required number of balls. Over goes the machine again and into the top bearing are poured another circle of balls, the ball head clip is pushed on and the locking nut screwed on, and the machine is ready for handlebar, saddle pillar, etc. The accessories are always fitted last, and then the machine goes to the viewer. This man is, or should be, a practical cyclist as well as a practical mechanic. He seizes the machine and after weighing it, entering its number in a book, and feeling the steering, he proceeds to test all the bearings and the chain for correct adjustment, bangs the machine up
The Cycle Industry (1921) p57.jpg

Fig. 15
This photograph is one of the Rudge-Whitworth floors of an extensive building

and down and about, tries the brakes, pinches the tyres, runs an eye over all, and finally passes it along to the women and girls who proceed to grease it, wrap strips of paper or butter cloth all over it and tie it up with string. If it is going overseas and the journey is long, the machine may have to be dissembled to enable it to be packed with others in metal lined cases. For passenger train in the British Isles it goes forward wrapped in paper or cloth and for goods train in a crate, either singly or with two or three others.

For transit by goods train in Great Britain each machine occupies a narrow wood crate; by removing pedals and handle-bar it is possible to squeeze a bicycle into a space of 77 in. × 23 in. × 48 in., or 48½ cu. ft. If two or more machines are to travel together the separate crates are sometimes enclosed in another wood crate that is strong enough to hold the lot and to allow it to be slung, and there you are.