Outspinning the Spider: The Story of Wire and Wire Rope

by John Kimberly Mumford

To the novice, wire is wire. Here he learns that what is wire for one thing is valueless for another and wire that looks to the unpracticed eye as if it were ready for market always has to undergo a few more processes before it is up to demands. Wherever, however far, you travel in this succession of high-roofed, airy buildings, you come always upon some new regiment of machines, some new container of chemical or metal, with a long line of reels unwinding wire to undergo some additional treatment. And always moving among the buildings are cars, big and little, packing wire or material from one place to another, to feed the wheels and furnaces. The tonnage from plant to plant and from house to house in the Roebling works would make a first-class annual business for many a modest railroad, even if it carried nothing else.

INSULATION

But when wire is finished it isn’t always finished. Since electricity spread itself over the earth in a million services, insulation in various forms has come to be almost as important as the wire itself. Insulation in its more advanced forms is a complex affair, gauged to accord with specific conditions and multiplying processes to secure the maximum of protection, both from electric current to life and property and from dampness and abrasion to the wire itself. In the making of wire screens the wire men have taken a leaf from the cloth-mill book, but in weaving a casing of cotton or other fibre around the wire for insulation the process is strongly reminiscent of some of the New England textile mills. Long rows of machines, black and silent and swift, reaching upward toward the ceiling, revolving rapidly on an upright shaft; long arms trailing downward, with wheels and bobbins like fingers plying dizzily but swiftly in and out around the wire which unwinds from its spool and keeps forever climbing. It is all like a Maypole, and the bobbins go in and out like children carrying each its ribbon. As the wire climbs, the whirling fingers braid around it a coating, tight fitting and impervious. Sometimes, where double insulation is required, there are two sets of arms, one above the other, the upper one putting on a second covering outside the first, of cotton of one color or another, or hemp or whatever else the experimentalists have found best for the purpose. You wonder how the bellcord in the railroad train can ever stand the pulling and jerking and wear and tear it gets. It is simple. It is just a perfectly made and highly tinned wire rope, with a double coat of braided cotton over it. The jacket may wear off in time, but the Roebling rope inside will never fail in a lifetime to get the message to the engineer.

When these snug coverings are finished the wire for certain uses is taken to another part of the works where it is unwound once more to pass through a bath of asphalt compound. After this process, which leaves a dull, dirty-looking surface, the spools of treated wire are put aside for drying, and then a final surfacing applied. The next journey is to the packing room.

TELEPHONE CABLES

Insulation is a wide range business. It cases wire in asbestos to prevent fire from stopping its work; but perhaps the highest phase is reached in the great cables of copper wires used in telephone service. For these the individual wires are covered with paper of various colors, which serves not only for protection but enables men at the opposite ends of a long cable to pick out unerringly the wires with which connection is to be made. Colors are few but possible combinations are many. The machining of this is more than ever like the Maypole, with pink and blue and yellow strips of paper flashing in the shadows. When the wires, paper covered, are brought together in the cable, sometimes three or four hundred of them altogether, the whole goes through the taping machines, which apply one or two suits of what may be called “underwear,” for after it has been covered with two or three different materials there remains a suit of lead to be fitted, and this is a big work done deftly.

Who has not seen men in the streets dragging huge pipes of lead through the open manholes from big wooden spools? These are the cables you talk over. They have been papered and clothed—and tarred and feathered, maybe—and then encased in lead by a process that is so easy as to be laughable, and yet as ingenious as any one thing the wire miller does. Unrolling slowly from its spool, the heavy cable moves up to a machine built strong and four-legged from the floor. In the mid height of this, a few feet above the floor, is a square chamber containing molten lead. The cable passes in at the rear and upward. It requires some credulity to believe that it is the movement of the molten lead that carries the cable along, but in any case when it emerges from the “box,” through an aperture that trims the soft metal down to uniformity, it has a solid lead covering as even as lead pipe, and at the point of egress cold water playing from just above cools it. Then it passes on through a long tank of water for final hardening and is wound slowly, clean and shining, on the great spools that are to carry it to market.

Many astonishing things are done in wire works, but done so swiftly, and smoothly and in such volume that they look easy. The man in the street, hurrying about his own business, never even takes time to wonder to himself how they are accomplished.

CHAPTER V
WIRE ROPE—THE GIANT

“Pig” and “ore” and melting materials, with a condiment of carbon, are the body and bones of steel wire. Their virtues, combined and intensified by tireless processes, and tested unsparingly at every stage, are united in wire rope; and wire rope, when all is said and done, is the mighty backbone of the wire industry.