A pin is a device used for fastening objects or material together. Pins often have two components: a long body and sharp tip made of steel, or occasionally copper or brass, and a larger head often made of plastic. The sharpened body penetrates the material, while the larger head provides a driving surface. It is formed by drawing out a thin wire, sharpening the tip, and adding a head. Nails are related, but are typically larger. In machines and engineering, pins are commonly used as pivots, hinges, shafts, jigs, and fixtures to locate or hold parts.
Sewing and fashion pins
The development of the pin closely paralleled that of its perforated counterpart, the needle. Archaeological evidence suggests that curved sewing pins have been used for over four thousand years. Originally, these were fashioned out of iron and bone by the Sumerians and were used to hold clothes together. Later, pins were also used to hold pages of books together by threading the needle through their top corner.
Many later pins were made of brass, a relatively hard and ductile metal that became available during the Bronze Age. This development was followed by the use of steel which was much stronger but tended to rust when exposed to humid air. The development of inexpensive electroplating techniques allowed the steel to be plated with nickel. Nickel did not rust, but tended to flake off the steel in humid weather, again allowing it to rust. However, this took many months or even years to happen, and as nickel plated steel pins were usually used only temporarily to hold fabric in place prior to sewing, no further refinement has been considered necessary. Note, however, that some modern specialty pins are made out of rust-proof and very strong titanium.
Walter Hunt invented the safety pin by forming an eight-inch brass pin into a bent pin with a spring and guard. He sold the rights to his invention to pay a debt to a friend, not knowing that he could have made millions of dollars.
|Pin type||Typical size[Note 1]||Typical length||Features|
|Beading pins||14||.875 inches (22.2 mm)||Wider-than-usual-head allows this pin to hold beads more easily|
|T-pins||0.75 mm||1.25 inches (32 mm)||A pin with a head bent into a capital letter "T" to make it easier to grab with the finger tips|
|Dressmaker pins||17-20||1.0625 inches (26.99 mm)||The most common type of sewing pin, used for light to medium-weight fabrics; may have either a small flat head or a round plastic one|
|Pleating pins||17||1.0625 inches (26.99 mm)||Considered "extra fine", used for pinning pleats and lightweight fabrics|
|Applique pins||0.6 mm||.75 inches (19 mm)||These pins have small round white glass heads that are easy to work around; also, because the pins are comparatively short they are less likely to "stick out" when holding small pieces of fabric against a larger one|
|Bridal and lace pins||17||1.25 inches (32 mm)||These pins are made entirely of stainless steel and will not rust; used for fine and lightweight fabrics|
|Patchwork pins||22 (.5 mm)||1.4375 inches (36.51 mm)||Pins have extra sharp tips for penetrating thick iron-on patches; their size and length also make them suitable for quilting; they have glass heads that will not melt if pressed in an iron|
|Quilting pins||30 (.6 mm)||1.875 inches (47.6 mm)||Quilting pins are exceptionally long and often have glass heads|
|Silk pins||0.5 mm||1.4375 inches (36.51 mm)||Pins suitable for lightweight fabrics; glass head will not melt when ironed|
|Pearlized pins||24||1.5 inches (38 mm)||These have round plastic heads which have been painted (often in bright colors) to superficial resemble the appearance of pearls|
|Sequin pins||8 (0.5 mm)||.5 inches (13 mm)||Exceptionally short length makes these pins suitable for applique; large flat head makes them able to hold sequins in place|
|Tidy pins||-||1.5 inches (38 mm)||U-shaped pins with no head used for holding slip covers and doilies in place; often made of brass so that they will not rust;also called fork pins|
|Hatpins||-||20 centimetres (7.9 in)||Exceptionally long decorative pin used to hold a woman's hat in place|
General purpose pins
Steel pins without heads
Thin, hardened pins can be driven into wood with a hammer with the goal of not being seen.
A different style pin, somewhat thicker (1.5–2 mm diameter), 2 cm short and with rounded tip (known as a stylus) is used with gramophones. The vibration of the stylus transforms the physical waves of the groove in a record to the movement of a membrane. In this way the sound recorded can be heard.
In engineering and machine design, a pin is a machine element that secures the position of two or more parts of a machine relative to each other. A large variety of types has been known for a long time; the most commonly used are solid cylindrical pins, solid tapered pins, groove pins, slotted spring pins and spirally coiled spring pins.
- The size numbers given here correspond to those found on the packaging of various manufacturers-- they do not necessarily correspond to any objective width measurement or to the size numbers of other manufacturers. Measurements given in millimeters are actual millimeters.
- Petroski, Henry, "From Pins to Paper Clips", The Evolution of Useful Things, Knopf, New York, 1993, p. 53
- Bridgman, Roger. 1000 Inventions & Discoveries. New York: Dorling Kindersley Publishing , 2002, p.126
- Alfred, R (2008-10-04). "April 10, 1849: Safety Tech Gets to the Point, Baby". Wired. Retrieved 2008-10-23.