Wrenches & Spanners Origins
How open-end, box-end, combination and adjustable wrenches developed for automotive work.
Where did the term "monkey wrench" come from?
Short answer: The exact origin of the name "monkey wrench" is uncertain, and stories about an inventor named "Monk" or "Moncky" are generally treated as folklore.
The exact origin of the name "monkey wrench" is uncertain, and stories about an inventor named "Monk" or "Moncky" are generally treated as folklore. What is documented is that adjustable screw wrenches were in use in the early 1800s, and Loring Coes of Worcester, Massachusetts patented an improved screw wrench design in the 1840s that became widely copied.
Who was Loring Coes and why does he matter in wrench history?
Short answer: Loring Coes was a Worcester, Massachusetts toolmaker who patented an improved adjustable screw wrench in the 1840s.
Loring Coes was a Worcester, Massachusetts toolmaker who patented an improved adjustable screw wrench in the 1840s. The Coes wrench design, with a sliding jaw moved by a threaded screw, became one of the best-known "monkey wrench" patterns and was produced for decades, appearing in many early automobile and farm tool kits.
Who invented the pipe wrench?
Short answer: Daniel C. Stillson is credited with patenting the modern pipe wrench in 1869.
Daniel C. Stillson is credited with patenting the modern pipe wrench in 1869. His design used a floating hook jaw that bites harder as force increases, which made it ideal for round pipe. The Stillson pattern became so common that "Stillson wrench" was used as a generic name for pipe wrenches for generations.
Who designed the modern Swedish adjustable wrench?
Short answer: Swedish inventor Johan Petter Johansson is credited with developing the modern adjustable wrench design in the early 1890s.
Swedish inventor Johan Petter Johansson is credited with developing the modern adjustable wrench design in the early 1890s. His wrenches were produced by the company that became Bahco, and the slim-jawed design spread worldwide, which is why adjustable wrenches are still called "Swedish keys" in some countries.
Why is an adjustable wrench often called a "Crescent wrench" in the United States?
Short answer: The Crescent Tool Company of Jamestown, New York began making adjustable wrenches in the early 1900s, and its product became so popular that "Crescent wrench" turned into a generic term in North America.
The Crescent Tool Company of Jamestown, New York began making adjustable wrenches in the early 1900s, and its product became so popular that "Crescent wrench" turned into a generic term in North America. The brand still exists today, and the name remains a common shop nickname for any adjustable wrench.
Who founded the Crescent Tool Company?
Short answer: The Crescent Tool Company was founded in Jamestown, New York in 1907 by Swedish-born Karl Peterson.
The Crescent Tool Company was founded in Jamestown, New York in 1907 by Swedish-born Karl Peterson. Its adjustable wrench became one of the most recognizable tools in American garages, and the company later became part of larger tool groups while keeping the Crescent brand name.
How did early automobiles change the wrenches mechanics carried?
Short answer: Early automobiles borrowed tools from carriage, bicycle and machine shops, so the first car tool kits often held adjustable and open-end wrenches.
Early automobiles borrowed tools from carriage, bicycle and machine shops, so the first car tool kits often held adjustable and open-end wrenches. As cars standardized their fastener sizes, mechanics shifted toward fixed-size open-end, box-end and combination wrenches that fit more securely and were less likely to round off nuts.
Why did box-end and combination wrenches become standard in auto shops?
Short answer: A box-end wrench surrounds the fastener and grips all six flats or points, while an open-end wrench grips only two.
A box-end wrench surrounds the fastener and grips all six flats or points, while an open-end wrench grips only two. As engines used higher torque values and more corrosion-prone fasteners, box-end and combination wrenches became standard because they were less likely to round off a stubborn nut.
When did combination wrenches become standard in auto shops?
Short answer: Combination wrenches, with an open end on one side and a box end of the same size on the other, became a standard professional tool during the first half of the twentieth century.
Combination wrenches, with an open end on one side and a box end of the same size on the other, became a standard professional tool during the first half of the twentieth century. They let a technician break a fastener loose with the box end and spin it quickly with the open end, which made them a staple of every mechanic's set.
Why were flare nut wrenches developed?
Short answer: Flare nut wrenches, also called line wrenches, were developed for the soft brass and steel fittings on brake, fuel and hydraulic lines.
Flare nut wrenches, also called line wrenches, were developed for the soft brass and steel fittings on brake, fuel and hydraulic lines. They look like a box-end wrench with a slot cut so they can slip over tubing, and they grip more flats than an open-end wrench, which reduces the risk of rounding delicate tube nuts.
When did ratcheting box wrenches become popular in auto repair?
Short answer: Ratcheting box wrenches existed in various forms for decades, but they became mainstream in automotive shops in the 1990s when ratcheting combination wrenches with fine-tooth mechanisms were widely marketed, with GearWrench being one of the best-known brands.
Ratcheting box wrenches existed in various forms for decades, but they became mainstream in automotive shops in the 1990s when ratcheting combination wrenches with fine-tooth mechanisms were widely marketed, with GearWrench being one of the best-known brands. They let technicians turn fasteners without lifting the wrench off, saving time in cramped engine bays. Follow the manufacturer's safety instructions when using this equipment.
How did obstruction wrenches develop as engine bays got crowded?
Short answer: Obstruction wrenches have bent, offset or curved handles that reach fasteners blocked by other components.
Obstruction wrenches have bent, offset or curved handles that reach fasteners blocked by other components. Their variety grew as engine compartments became more crowded, especially for starter, manifold and bell-housing bolts that straight wrenches could not reach.
Why was the tappet wrench common in older auto shops?
Short answer: Older engines with solid lifters and adjustable rocker arms needed their valve lash set regularly during tune-ups.
Older engines with solid lifters and adjustable rocker arms needed their valve lash set regularly during tune-ups. Thin open-end tappet wrenches fit the lock nuts on these adjusters, so they were common in shops for decades. They became less essential as hydraulic lifters and non-adjustable valvetrains spread.
Why did early cars come with their own tool kits?
Short answer: Early automobiles were unreliable and repair shops were scarce, so manufacturers often supplied a tool roll with wrenches, pliers, a screwdriver and tire tools.
Early automobiles were unreliable and repair shops were scarce, so manufacturers often supplied a tool roll with wrenches, pliers, a screwdriver and tire tools. Owners were expected to make roadside repairs themselves, and these kits are now prized by collectors restoring period-correct cars.
How did crowfoot wrenches come into use with torque wrenches?
Short answer: Crowfoot wrenches are open-end or flare-nut heads that fit a square drive.
Crowfoot wrenches are open-end or flare-nut heads that fit a square drive. They came into common use for reaching fittings where a socket cannot fit, such as line fittings and some manifold nuts, and for torquing those fasteners with an extension and torque wrench.
General guidance only. Follow the vehicle and tool manufacturer's procedures, and confirm vehicle coverage on the tool maker's list before buying.