Bowling pins (historically also known as skittles or kegels) are upright elongated solids of rotation with a flat base for setting, usually made of wood (esp. maple) standing between 9 and 16 inches (23 and 41cm) tall. Some have interior voids to adjust weight and balance. Pins are coated with plastic and painted, by convention mostly white with (usually) transaxial red stripes or other markings around the neck or middle (candlepins). Sets of pins, usually 5, 9, or 10 in a triangular arrangement, are the target of the bowling ball in various bowling games including tenpins, five-pins, duckpins and candlepins.
Tenpins
Ten-pin bowling pins shown at different stages of manufacture. From right to left: a lathe shapes a pin from a block of wood before it is coated with plastic. Inner voids (spaces affecting center of gravity and tipping point) are also visible.[1]
Tenpins to scale on a bowling lane
Pin specifications are set by the United States Bowling Congress (USBC). World Bowling, formerly World Tenpin Bowling Association, has adopted the USBC specifications. Pins are 15 inches (380 mm) tall, 4.75 inches (121 mm) wide at their widest point, and weigh 3 pounds 8 ounces (1.6 kilograms) ±2 ounces (0.057 kilograms).[2] The first British made tenpin was by H Massil and sons who received the permit no.1 from the British Tenpin Bowling Association (BTBA)[3]
The USBC indicated that, effective August 1, 2023, it is certifying string pinsetters and string pin bowling as an independent category of equipment and competition separate from conventional free-fall pinsetters.[4] USBC lab data indicated strike percentage on string pin bowling is 7.1% lower, causing the USBC to plan additional testing to determine whether a scoring conversion should be created between the categories.[4] String pinsetters are less expensive and easier to maintain, motivating bowling centers to phase them in.[5]
Duckpins and fivepins
Duckpins (displayed closer than they would be placed on a bowling lane)
Duckpins on a bowling lane
Duckpins are shorter and squatter than standard tenpins. Canadian fivepins are between duckpins and tenpins in size, but have a thick, inch-wide rubber band around the widest part of the pin to increase pin action when struck.
Candlepins
A full rack of ten candlepins, with the sport's small ball.
Candlepins to scale on a bowling lane
Candlepins are dissimilar to the others, being the tallest of all at 15+3⁄4 inches (40 cm), but only 2+15⁄16 inches (7.5 cm) wide and 2 lb 8 oz (1.1 kg) in weight, each pin nearly matching the maximum weight of a candlepin ball.[6] They are nearly cylindrical in shape with a slight taper toward either end, making them vaguely resemble candles (hence the name). Unlike other bowling pins, because they are vertically symmetrical, candlepins may be set on either end. Due to their width and construction, candlepins tends to produce a billiard ball-like sound when struck.
Kegels
Pins used in the German bowling game kegel appears to combine the design of tenpins and duckpins. The overall shape of the pin resembles a standard ten-pin bowling pins, and its small size is comparable to duckpins. Similar to five-pin bowling, these pins have strings attached on top of each, which connects them to the pinsetter.
Pin construction
Bowling pins are constructed by gluing blocks of rock maple wood into the approximate shape, and then turning on a lathe. After the lathe shapes the pin, it is coated with a plastic material, painted, and covered with a glossy finish. Because of the scarcity of suitable wood, bowling pins can be made from approved synthetics. Currently there are synthetic pins sanctioned for play in five-pin, duckpin, and candlepin. There is one synthetic ten pin model approved by the USBC. When hit by the ball, synthetic pins usually sound different from wooden pins.
Juggling clubs could be mistaken for bowling pins due to their similar shape. The two differ greatly in construction and weight.