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Rubber band



  A rubber band (in some regions known as a binder, elastic band, lackey band or gumband in Pittsburgh, as well as some parts of Australia) is a short length of rubber and latex formed in the shape of a loop. Such bands are typically used to hold multiple objects together. The rubber band was patented in England on March 17, 1845 by Stephen Perry.

Additional recommended knowledge

Contents

Manufacturing

The manufacturing process involves extruding the rubber into a long tube to provide its general shape, putting the tubes on mandrels and curing the rubber with heat, and then slicing it along the width of the tube into little bands.[1][2] While other rubber products may use synthetic rubber, rubber bands are still primarily manufactured using natural rubber because of its superior elasticity.

The modern rubber band is different from its ancestor at the time of patenting by Stephen Perry in that rubber is now vulcanized. The vulcanization process makes the rubber more durable and elastic, and therefore makes the rubber band more useful.

Rubber Band Sizes

Measuring

  A rubber band has three basic dimensions: Length, width, and thickness. (See picture.)

A rubber band's length is half its circumference.

Its thickness is the distance from the inner circle to the outer circle.

Lay a rubber band down so that it makes a circle. The band's width is the height of that band or cylinder. If one imagines a long tube of rubber before it is sliced into rubber bands, the band's width is how far apart the slices are cut.

Rubber Band Size Numbers

A rubber band is given a [quasi-]standard number based on its dimensions.

Generally, rubber bands are numbered from small to large, width first. Thus, rubber bands numbered 8-19 are all 1/16 inches wide, with length going from 7/8 inches to 3 1/2 inches. Rubber band numbers 30-34 are for width of 1/8 inches, going again from shorter to longer. For even longer bands, the numbering starts over for numbers above 100, again starting at width 1/16 inches.

The origin of these size numbers is not clear and there appears to be some conflict in the "standard" numbers. For example, one distributor[3] has a size 117 being 1/16 inch wide and a size 127 being 1/8 inch wide. However, an OfficeMax size 117[4] is 1/8 inch wide. A manufacturer[5] has a size 117A (1/16 inch wide) and a 117B (1/8 inch wide). Another distributor[6] calls them 7AA (1/16 inch wide) and 7A (1/8 inch wide) (but labels them as specialty bands).

Rubber Band Sizes
Size Length (in) Width (in) Thickness (in)
10 1.25 1/16 1/32
12 1.75 1/16 1/32
14 2 1/16 1/32
31 2.5 1/8 1/32
32 3 1/8 1/32
33 3.5 1/8 1/32
61 2 1/4 1/32
62 2.5 1/4 1/32
63 3 1/4 1/32
64 3.5 1/4 1/32
117 7 1/16 1/32

Uses

Because of the rebound property resulting from a rubber band's elasticity, the rubber band has numerous uses, many recreational and others serious.

 

  • Rubber bands can be used as projectiles. The easiest way of doing this is to place one end on the thumb or index finger and stretch the other with the opposite hand. When the latter end is let go, the band will release. Rubber band guns also exist to fire rubber bands, and are generally more accurate. Rubber bands sting if shot at point-blank range against bare skin, but are generally harmless. However, it is best to avoid firing them at another person's face or eyes, bare skin, or at close range. As projectiles, rubber bands are sometimes used in intra-office or school pranks, involving employees or students with many dozens of rubber bands being shot at or between other various employees or students. Rubber bands can also shoot small projectiles, such as paper wasps, paper wads, spit wads, pens, pencils, paper clips, coins, rings, small animal shaped toys, etc.
  • A rubber band, although it can be very thin, does have a non-zero thickness. Therefore, when a rubber band is fixed on two ends and then twisted upon itself, it is equivalent to being stretched. As a result, the band will try to unstretch by untwisting itself. Based on this property, rubber bands are sometimes used to power model aircraft or other mechanical toys. When the rubber band untwists itself, it will rotate the propeller affixed to it.
  • Rubber bands last longer when kept refrigerated
  • A common way to suspend hard drive(s) in a computer case is to use rubber bands. Suspending hard drive(s) avoids contact between the hard drive(s) and the computer case. This results in reducing vibrations to the case, which reduces noise in the computer case.
  • Rubber bands are often used in orthodontics to help realign teeth over a period of time.
  • A makeshift eraser can be made by wrapping a rubber band tightly around the end of a pencil.
  • Rubber bands can be tied together to create a Chinese jump rope. Many rubber bands wrapped one by one around a core will form a bouncy rubber band ball.
  • Rubber bands are used during aerobic exercising as fitness tools.
  • Rubber bands can also be worn around the wrist as bracelets.

References

  1. ^ How rubber bands are made. This reference states that the rubber is vulcanized before it is extruded.
  2. ^ Lee Rubber Products, How rubber bands are made. This reference states that the rubber is vulcanized after it is extruded.
  3. ^ BigWig Enterprises, BigWig Size Chart
  4. ^ OfficeMax, #OM97352, UPC 011491-973520
  5. ^ Lee Rubber Products, How do rubber bands measure up?
  6. ^ Dykema Rubber Band
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Rubber_band". A list of authors is available in Wikipedia.
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