Shoelace
Background
It is understand how important shoes are for protecting feet from hazards and weather, and proper fit is necessary to maximize protection and comfort for the shoe’s wearer. The shoelace is one way to ensure the proper fit, and a simple pair of laces, costing less than two dollars, can make all the difference in the world to the look and fit of a shoe. The lace is just a simple, woven band that pulls the shoe together to hold it to the foot. A shoelace consists of only two components: the woven tape that pulls the shoe tightly together, and the aglet, the hardened, taped end that fits through the eyelets on a shoe or boot.
Shoelaces have surprising importance in our lives. A real watershed in a child’s life is when he has finally learned to tie his shoes. Athletes are vehement about checking and double-checking shoelaces before races or other fast-moving events lest they trip on them or take time on the field to retie them. American championship skater Tonya Harding nearly forfeited time on the ice during championship competition in 1994 because her skate lace had broke and her skate fit improperly.
Shoelaces are still manufactured in the United States although they are also made overseas where labor is cheaper. They are made in one of two ways in the United States The more common method includes the old-fashioned braiding of the shoelace using bobbins on machines that may be decades old. It is a simple process but still effective in producing significant numbers of laces a day. This method permits extensive variation within lace manufacture—one may vary fibers used, color, the number of ends or yarns, and design as desired to produce an array of laces. Recently, some new machinery has been developed for the completely computerized weaving of a shoelace on a narrow fabric loom. Much of this machinery is European in manufacture and it is not universally adopted in the United States (wholesale replacement of older machinery by an established company would be quite an investment).
History
The history of shoelaces is inextricably bound with the history of the shoe and how it was secured and designed in different eras and cultures. In 2000 b.c., ancient Mesopotamians wore simple pieces of leather that fit beneath the foot and were bound to the foot and ankle with laces that were likely of rawhide. Without these laces, the soles were useless. The footwear of ancient Greeks included sandals with rawhide lacing, and the ancient Etruscans donned high-laced shoes with turned-up toes. Roman soldiers spread the use of shoes to western Europe, particularly the utilitarian footcovering of the marching soldier. Ancient Britons adopted the Romans’ simple sole with a thong between the large toe and second toe, with rawhide straps securing the sandal to the foot. There was a fair variety of laced shoes during this period, including shoes of more luxurious fabrics and furs that have not survived. Many of the more expensive shoes were secured with pins rather than laces. Both ancient Romans and Greeks deplored carelessness in appearance, and those with haphazardly tied laces were ridiculed.
Shoes of the Middle Ages are less frequently found in excavations than those of the Romans, perhaps because the sturdy leather of the Roman sandal seems to defy deterioration. Nevertheless, there was a variety of footwear during this era as well. The poor went without shoes. Other shoes were actually breeches of linen that were laced to the leg and down over the foot, leaving the toes exposed. Other shoes were moving toward boots, covering the upper portion of the foot, and strapped together. Later in the Middle Ages, cordwainers (shoemakers) were able to fit boots and shoes of the wealthy more precisely and some of these shoes were secured with buttons or just a few short laces.
In the Elizabethan era, shoes were often secured with straps, laces, buckles and pins—both plain and jeweled. Prosperous American colonists generally secured their colored leather or fabric shoes with buckles or ribbons, while those with less money wore sturdy, simple leather shoes and boots tied with short rawhide laces. Eyelets for shoelaces, which guided shoelaces as they passed through the shoe, were hand-sewn of sturdy thread until about the 1840s, when metal eyelets were developed. Victorian boots for women were secured in a variety of ways. Popular gaiters actually used elastic gores that made it easy to pull the boots on and off, and that held the boots tight to the feet. Button boots were popular, as were ankle-high boots with metal eyelets for fabric laces. Shoes and laces were mass-produced in New England, particularly Massachusetts and New Hampshire, around the time of the Civil War. Textile braiding machinery, constructed by New England firms for the purpose of making shoelace braid, was readily available. Some of it is still in use in this country as the basic process of weaving the shoelace braid has changed little, even though fibers and colors have changed.
Raw Materials
The materials used for shoelaces vary according to the type of lace under construction. Typical fibers used for laces today include cotton, textured polyester, spun polyester, nylon, and polypropylene. The aglet, the hard plastic end of the shoelace that pushes through the eyelet in the shoe, is made of clear plastic. Acetone is used in the process of securing the aglet to the braided lace.
The Manufacturing Process
This essay will discuss the method of shoelace manufacture that uses a braiding machine to make shoelaces. It should be noted that the tipping and cutting of the woven braid described below is fairly standard across American factories.
- First, there is a large room filled with dozens of shoelace braiding machines. Each machine resembles a horizontal circle and is equipped with 44 bobbins that all contribute to the manufacture of a single shoelace. Attached to the machine is a basket that will catch the shoelace as it is woven.
- Next, the braiding begins. Electric motors start the braiding machinery. The bobbins start weaving the thin shoelace, with the braiding action resembling a maypole as the bobbin thread is deployed in a specific order. Side gears on the machine tell the machine how fast to take up the yarn to vary the tightness of the weave. The more quickly the yarn is taken up, the looser the braid. As the braid becomes longer and longer, it falls directly into a can that holds it there until the braid is finished. Each braiding machine can produce about a gross (144 shoelaces) every thirty minutes. Generally, the can holds about 13 lb (5.9 kg) of braid. The amount of braid this basket may hold varies according to thickness of the braid. Heavy sport laces, such as hockey laces, quickly add up to 13 lb (5.9 kg).
- The cans of braids are moved to the tipping department. Each piece of braid is put into a machine that performs a variety of functions. First, the automatic tipping machine immerses the braid in acetone. (The acetone will allow the braid to hold the plastic tip tightly.) Then, the braid is automatically inserted into a die that holds acetate tape. The die is heated and presses the acetate tape at specific intervals (the length of the shoelace). Together, the acetone, the heat and the die pressure ensure that the shoelace will accept the acetate permanently. So, the braid is one long piece of shoelace that has a clear, 1-in (2-cm) wide band of acetate every 30 in (76 in) or so. Now the shoelaces are hung on the machine to dry (the acetone must evaporate) for about 20 minutes before the long braid is cut apart.
- The laces move along and another die advances and cuts each band of acetate in half. Thus, each aglet is now about 0.5 in (1.3 cm) wide (the acetate band was about I in (2 cm) wide but was cut in half). The process of cutting the aglet in half cuts apart the shoelaces as well. The laces fall into a basket as they are cut. The basket counts the laces as they are dropped in. One basket can hold a half a gross of laces at a time.
- Now the lace must be paired up. An operator takes two baskets, or one gross, of shoelaces, and places the baskets on his or her lap. Then, the operator takes a lace in the right hand and one in the left, and feeds them into a pairing machine. The laces are sucked up into this elevator at right and left, are wound around a cardboard cylinder as a pair, and are pushed through a chute for packaging.
- The pair of laces wound on a cardboard cylinder are sent to the blister packaging machine. Cardboard is put behind the laces, polystyrene in front, and the package is heat-sealed. The pairs are sent to a cardboard shipping box for movement out of the factory.
Quality Control
Control of product varies by factory and method of production. However, one company that utilizes braiding machines controls quality in three ways. First, the most important way that the employees control quality is in monitoring the bobbins as they weave the braid. When the bobbin is empty it drops down and the action stops until a new bobbin is put on. However, the new yarn must be knotted into the braid to continue the weaving. The operator ties a large knot into the shoelace so that the flaw is noticeable. The operator must remove that shoelace with a knot before it moves into the automatic tipping machine, or the big knot will explode the heated metal die (it is too bulky for the die).
Also, operators inspect each and every shoelace that is produced. Some laces are dirty and if so, they are removed and considered flawed. Inspection occurs when the laces are hanging to dry and as the operator is sending them into the pairing machine.
Maintaining machinery is essential to the successful operation of the business. The older braiding machines are decades old and are still efficient and precise because they are thoroughly cleaned and oiled each week.
By products/Waste
Those companies that dye their own yarns must deal with the liquid effluvia ejected from their factory and reclaim the water. Bleaches and dyes are an environmental concern, and governmental authorities monitor their disposal. Acetone disposal, should there be any, is also a concern. Some shoelace companies even produce their own cardboard packaging (others purchase it). One such company has been cited for using solvent-based coatings for the cardboard and causing environmental problems as a result. The company has been urged to move to water-based cardboard coatings.
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